AM335x OMAP2 common clock external fixed-clock registration

Greetings,

I have developed an AM3354 based SoM and it uses an external SI5351 clock generator to drive the clock inputs for an external duart and I2S audio master clock. With the registration according to the documentation the reference clock is not being detected and hence the clock generator is not working as expect.

After trying many different things, I started to look around the mailing lists to find information related to this issue.

I came acrossed post that has the exact same issue:
https://lkml.org/lkml/2013/2/18/468

Seeing as the patch did not land upstream, I am wondering if there is a solution that I am not seeing.

I am willing to provide a patch given appropriate guidance.

Regards,

Michael

Hi Michael,

The info on the email you referenced is kind of obsolete, TI SoCs are calling of_clk_init() during boot now, and thus external clock nodes should be registered fine also. Maybe you can provide the actual DTS patch you are trying out so we can help better...? Are you seeing any boot time error / warning prints for your new clock?

-Tero

See attached patch and console output.

With the debug messages on you see that the reference clock is not being detected.

Whilest debugging I found that the of_clk_get is returning an error no matter which clock I pass it:
http://lxr.free-electrons.com/source/drivers/clk/clk-si5351.c#L1131

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U-Boot SPL 2015.04-rc2-00210-g26fcaa0-dirty (Mar 18 2015 - 15:49:29)

U-Boot 2015.04-rc2-00210-g26fcaa0-dirty (Mar 18 2015 - 15:49:29)

Watchdog enabled

I2C:   ready
DRAM:  512 MiB
MMC:   OMAP SD/MMC: 0, OMAP SD/MMC: 1
SF: Detected N25Q128 with page size 256 Bytes, erase size 64 KiB, total 16 MiB
Net:   cpsw, usb_ether
Hit any key to stop autoboot:  0 

cpsw Waiting for PHY auto negotiation to complete.. done
link up on port 0, speed 100, full duplex
Using cpsw device
TFTP from server 192.168.1.1; our IP address is 192.168.1.2 Filename 'zImage-3354'.
Load address: 0x82000000
Loading: #################################################################

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         2.9 MiB/s

done
Bytes transferred = 5200008 (4f5888 hex)
Kernel image @ 0x82000000 [ 0x000000 - 0x4ed668 ]

Starting kernel ...

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 4.0.0-rc7-00016-g7b43b47-dirty (michael at deathray) (gcc version 4.9.1 (GCC) ) #11 SMP Tue Apr 14 18:51:01 CDT 2015
[    0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[    0.000000] Machine model: EMAC SOM-3354M SOM-200ES
[    0.000000] cma: Reserved 16 MiB at 0x9e800000
[    0.000000] Memory policy: Data cache writeback
[    0.000000] On node 0 totalpages: 130816
[    0.000000] free_area_init_node: node 0, pgdat c0a529c0, node_mem_map dfa71000
[    0.000000]   Normal zone: 1152 pages used for memmap
[    0.000000]   Normal zone: 0 pages reserved
[    0.000000]   Normal zone: 130816 pages, LIFO batch:31
[    0.000000] CPU: All CPU(s) started in SVC mode.
[    0.000000] AM335X ES2.1 (sgx neon )
[    0.000000] PERCPU: Embedded 12 pages/cpu @dfa18000 s18496 r8192 d22464 u49152
[    0.000000] pcpu-alloc: s18496 r8192 d22464 u49152 alloc=12*4096
[    0.000000] pcpu-alloc: [0] 0 
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 129664
[    0.000000] Kernel command line: console=ttyO0,115200n8 root=/dev/mmcblk0p1 ro rootfstype=ext4 rootwait debug earlyprintk=serial
[    0.000000] PID hash table entries: 2048 (order: 1, 8192 bytes)
[    0.000000] Dentry cache hash table entries: 65536 (order: 6, 262144 bytes)
[    0.000000] Inode-cache hash table entries: 32768 (order: 5, 131072 bytes)
[    0.000000] Memory: 482612K/523264K available (6794K kernel code, 642K rwdata, 2680K rodata, 444K init, 8243K bss, 24268K reserved, 16384K cma-reserved, 0K highmem)
[    0.000000] Virtual kernel memory layout:
[    0.000000]     vector  : 0xffff0000 - 0xffff1000   (   4 kB)
[    0.000000]     fixmap  : 0xffc00000 - 0xfff00000   (3072 kB)
[    0.000000]     vmalloc : 0xe0800000 - 0xff000000   ( 488 MB)
[    0.000000]     lowmem  : 0xc0000000 - 0xe0000000   ( 512 MB)
[    0.000000]     pkmap   : 0xbfe00000 - 0xc0000000   (   2 MB)
[    0.000000]     modules : 0xbf000000 - 0xbfe00000   (  14 MB)
[    0.000000]       .text : 0xc0008000 - 0xc0948e50   (9476 kB)
[    0.000000]       .init : 0xc0949000 - 0xc09b8000   ( 444 kB)
[    0.000000]       .data : 0xc09b8000 - 0xc0a58ac0   ( 643 kB)
[    0.000000]        .bss : 0xc0a58ac0 - 0xc12658b0   (8244 kB)
[    0.000000] Hierarchical RCU implementation.
[    0.000000]  Additional per-CPU info printed with stalls.
[    0.000000]  RCU restricting CPUs from NR_CPUS=2 to nr_cpu_ids=1.
[    0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[    0.000000] NR_IRQS:16 nr_irqs:16 16
[    0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts
[    0.000000] OMAP clockevent source: timer2 at 26000000 Hz
[    0.000017] sched_clock: 32 bits at 26MHz, resolution 38ns, wraps every 165191049177ns
[    0.000069] OMAP clocksource: timer1 at 26000000 Hz
[    0.000896] Console: colour dummy device 80x30
[    0.000950] Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar
[    0.000959] ... MAX_LOCKDEP_SUBCLASSES:  8
[    0.000967] ... MAX_LOCK_DEPTH:          48
[    0.000975] ... MAX_LOCKDEP_KEYS:        8191
[    0.000983] ... CLASSHASH_SIZE:          4096
[    0.000990] ... MAX_LOCKDEP_ENTRIES:     32768
[    0.000998] ... MAX_LOCKDEP_CHAINS:      65536
[    0.001005] ... CHAINHASH_SIZE:          32768
[    0.001012]  memory used by lock dependency info: 5167 kB
[    0.001021]  per task-struct memory footprint: 1152 bytes
[    0.001046] Calibrating delay loop... 996.14 BogoMIPS (lpj=4980736)
[    0.078896] pid_max: default: 32768 minimum: 301
[    0.079243] Security Framework initialized
[    0.079405] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes)
[    0.079420] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)
[    0.082267] Initializing cgroup subsys blkio
[    0.082310] Initializing cgroup subsys memory
[    0.082399] Initializing cgroup subsys devices
[    0.082495] Initializing cgroup subsys freezer
[    0.082618] Initializing cgroup subsys perf_event
[    0.082698] CPU: Testing write buffer coherency: ok
[    0.084030] CPU0: thread -1, cpu 0, socket -1, mpidr 0
[    0.084142] Setting up static identity map for 0x806748a0 - 0x80674910
[    0.087552] Brought up 1 CPUs
[    0.087575] SMP: Total of 1 processors activated (996.14 BogoMIPS).
[    0.087586] CPU: All CPU(s) started in SVC mode.
[    0.090919] devtmpfs: initialized
[    0.093098] VFP support v0.3: implementor 41 architecture 3 part 30 variant c rev 3
[    0.130337] omap_hwmod: tptc0 using broken dt data from edma
[    0.130713] omap_hwmod: tptc1 using broken dt data from edma
[    0.131067] omap_hwmod: tptc2 using broken dt data from edma
[    0.139043] omap_hwmod: debugss: _wait_target_disable failed
[    0.196258] pinctrl core: initialized pinctrl subsystem
[    0.230071] NET: Registered protocol family 16
[    0.235694] DMA: preallocated 256 KiB pool for atomic coherent allocations
[    0.237787] cpuidle: using governor ladder
[    0.237817] cpuidle: using governor menu
[    0.244784] gpiochip_add: registered GPIOs 0 to 31 on device: gpio
[    0.245577] OMAP GPIO hardware version 0.1
[    0.246826] gpiochip_add: registered GPIOs 32 to 63 on device: gpio
[    0.248668] gpiochip_add: registered GPIOs 64 to 95 on device: gpio
[    0.250522] gpiochip_add: registered GPIOs 96 to 127 on device: gpio
[    0.263655] omap-gpmc 50000000.gpmc: could not find pctldev for node /pinmux at 44e10800/pinmux_gpmc_pins, deferring probe
[    0.263699] platform 50000000.gpmc: Driver omap-gpmc requests probe deferral
[    0.267534] No ATAGs?
[    0.267564] hw-breakpoint: debug architecture 0x4 unsupported.
[    0.310333] edma-dma-engine edma-dma-engine.0: TI EDMA DMA engine driver
[    0.311153] of_get_named_gpiod_flags: can't parse 'gpio' property of node '/fixedregulator at 0[0]'
[    0.314814] SCSI subsystem initialized
[    0.315615] libata version 3.00 loaded.
[    0.316335] usbcore: registered new interface driver usbfs
[    0.316489] usbcore: registered new interface driver hub
[    0.316637] usbcore: registered new device driver usb
[    0.317421] omap_i2c 44e0b000.i2c: could not find pctldev for node /pinmux at 44e10800/pinmux_i2c0_pins, deferring probe
[    0.317459] platform 44e0b000.i2c: Driver omap_i2c requests probe deferral
[    0.321703] Switched to clocksource timer1
[    0.454603] NET: Registered protocol family 2
[    0.456449] TCP established hash table entries: 4096 (order: 2, 16384 bytes)
[    0.456627] TCP bind hash table entries: 4096 (order: 5, 147456 bytes)
[    0.457823] TCP: Hash tables configured (established 4096 bind 4096)
[    0.458016] TCP: reno registered
[    0.458043] UDP hash table entries: 256 (order: 2, 20480 bytes)
[    0.458214] UDP-Lite hash table entries: 256 (order: 2, 20480 bytes)
[    0.459115] NET: Registered protocol family 1
[    0.460640] RPC: Registered named UNIX socket transport module.
[    0.460661] RPC: Registered udp transport module.
[    0.460672] RPC: Registered tcp transport module.
[    0.460681] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.462896] hw perfevents: enabled with armv7_cortex_a8 PMU driver, 5 counters available
[    0.467119] futex hash table entries: 256 (order: 2, 16384 bytes)
[    0.467432] audit: initializing netlink subsys (disabled)
[    0.467656] audit: type=2000 audit(0.460:1): initialized
[    0.472263] VFS: Disk quotas dquot_6.5.2
[    0.472413] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[    0.474597] NFS: Registering the id_resolver key type
[    0.474963] Key type id_resolver registered
[    0.474978] Key type id_legacy registered
[    0.475147] jffs2: version 2.2. (NAND) (SUMMARY)  ?? 2001-2006 Red Hat, Inc.
[    0.479406] io scheduler noop registered
[    0.479439] io scheduler deadline registered
[    0.479491] io scheduler cfq registered (default)
[    0.481388] pinctrl-single 44e10800.pinmux: 142 pins at pa f9e10800 size 568
[    0.487822] pwm-backlight backlight: GPIO lookup for consumer enable
[    0.487848] pwm-backlight backlight: using device tree for GPIO lookup
[    0.487868] of_get_named_gpiod_flags: can't parse 'enable-gpios' property of node '/backlight[0]'
[    0.487881] of_get_named_gpiod_flags: can't parse 'enable-gpio' property of node '/backlight[0]'
[    0.487893] pwm-backlight backlight: using lookup tables for GPIO lookup
[    0.488064] pwm-backlight backlight: lookup for GPIO enable failed
[    0.488094] backlight supply power not found, using dummy regulator
[    0.492042] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    0.497622] omap_uart 44e09000.serial: no wakeirq for uart0
[    0.497656] of_get_named_gpiod_flags: can't parse 'rts-gpio' property of node '/ocp/serial at 44e09000[0]'
[    0.498244] 44e09000.serial: ttyO0 at MMIO 0x44e09000 (irq = 154, base_baud = 3000000) is a OMAP UART0
[    1.342107] console [ttyO0] enabled
[    1.347792] omap_uart 48022000.serial: no wakeirq for uart0
[    1.353813] of_get_named_gpiod_flags: can't parse 'rts-gpio' property of node '/ocp/serial at 48022000[0]'
[    1.363990] 48022000.serial: ttyO1 at MMIO 0x48022000 (irq = 155, base_baud = 3000000) is a OMAP UART1
[    1.377472] omap_rng 48310000.rng: OMAP Random Number Generator ver. 20
[    1.385070] [drm] Initialized drm 1.1.0 20060810
[    1.390764] panel panel: GPIO lookup for consumer enable
[    1.396416] panel panel: using device tree for GPIO lookup
[    1.402219] of_get_named_gpiod_flags: parsed 'enable-gpios' property of node '/panel[0]' - status (0)
[    1.411970] panel panel: found enable GPIO
[    1.422597] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    1.429523] [drm] No driver support for vblank timestamp query.
[    1.472792] Console: switching to colour frame buffer device 60x34
[    1.480225] tilcdc 4830e000.lcdc: fb0:  frame buffer device
[    1.486110] tilcdc 4830e000.lcdc: registered panic notifier
[    1.492027] [drm] Initialized tilcdc 1.0.0 20121205 on minor 0
[    1.524479] brd: module loaded
[    1.543800] loop: module loaded
[    1.552121] mtdoops: mtd device (mtddev=name/number) must be supplied
[    1.560212] of_get_named_gpiod_flags: parsed 'cs-gpios' property of node '/ocp/spi at 48030000[0]' - status (0)
[    1.570611] of_get_named_gpiod_flags: parsed 'cs-gpios' property of node '/ocp/spi at 48030000[1]' - status (0)
[    1.587500] gpiochip_find_base: found new base at 504
[    1.593627] gpiochip_add: registered GPIOs 504 to 511 on device: mcp23s08
[    1.602666] m25p80 spi1.0: unrecognized JEDEC id bytes: ff, ff, ff
[    1.610113] CAN device driver interface
[    1.617177] c_can_platform 481cc000.can: c_can_platform device registered (regs=fa1cc000, irq=160)
[    1.628530] usbcore: registered new interface driver asix
[    1.634458] usbcore: registered new interface driver ax88179_178a
[    1.640937] usbcore: registered new interface driver cdc_ether
[    1.647236] usbcore: registered new interface driver smsc95xx
[    1.653382] usbcore: registered new interface driver net1080
[    1.659400] usbcore: registered new interface driver cdc_subset
[    1.665743] usbcore: registered new interface driver zaurus
[    1.671794] usbcore: registered new interface driver cdc_ncm
[    1.679037] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[    1.685995] ehci-omap: OMAP-EHCI Host Controller driver
[    1.692040] usbcore: registered new interface driver cdc_wdm
[    1.698144] usbcore: registered new interface driver usb-storage
[    1.707480] am335x-phy-driver 47401300.usb-phy: GPIO lookup for consumer reset
[    1.715121] am335x-phy-driver 47401300.usb-phy: using device tree for GPIO lookup
[    1.722974] of_get_named_gpiod_flags: can't parse 'reset-gpios' property of node '/ocp/usb at 47400000/usb-phy at 47401300[0]'
[    1.734351] of_get_named_gpiod_flags: can't parse 'reset-gpio' property of node '/ocp/usb at 47400000/usb-phy at 47401300[0]'
[    1.745631] am335x-phy-driver 47401300.usb-phy: using lookup tables for GPIO lookup
[    1.753657] am335x-phy-driver 47401300.usb-phy: lookup for GPIO reset failed
[    1.761022] am335x-phy-driver 47401300.usb-phy: GPIO lookup for consumer vbus-detect
[    1.769128] am335x-phy-driver 47401300.usb-phy: using device tree for GPIO lookup
[    1.776967] of_get_named_gpiod_flags: can't parse 'vbus-detect-gpios' property of node '/ocp/usb at 47400000/usb-phy at 47401300[0]'
[    1.788884] of_get_named_gpiod_flags: can't parse 'vbus-detect-gpio' property of node '/ocp/usb at 47400000/usb-phy at 47401300[0]'
[    1.800708] am335x-phy-driver 47401300.usb-phy: using lookup tables for GPIO lookup
[    1.808726] am335x-phy-driver 47401300.usb-phy: lookup for GPIO vbus-detect failed
[    1.816722] 47401300.usb-phy supply vcc not found, using dummy regulator
[    1.828233] musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, bulk combine, bulk split, HB-ISO Rx, HB-ISO Tx, SoftConn)
[    1.839396] musb-hdrc: MHDRC RTL version 2.0 
[    1.843980] musb-hdrc: setup fifo_mode 4
[    1.848086] musb-hdrc: 28/31 max ep, 16384/16384 memory
[    1.853892] musb-hdrc musb-hdrc.0.auto: MUSB HDRC host driver
[    1.862785] musb-hdrc musb-hdrc.0.auto: new USB bus registered, assigned bus number 1
[    1.873128] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
[    1.880229] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[    1.887849] usb usb1: Product: MUSB HDRC host driver
[    1.893062] usb usb1: Manufacturer: Linux 4.0.0-rc7-00016-g7b43b47-dirty musb-hcd
[    1.900876] usb usb1: SerialNumber: musb-hdrc.0.auto
[    1.910221] hub 1-0:1.0: USB hub found
[    1.914819] hub 1-0:1.0: 1 port detected
[    1.925676] am335x-phy-driver 47401b00.usb-phy: GPIO lookup for consumer reset
[    1.933374] am335x-phy-driver 47401b00.usb-phy: using device tree for GPIO lookup
[    1.941204] of_get_named_gpiod_flags: can't parse 'reset-gpios' property of node '/ocp/usb at 47400000/usb-phy at 47401b00[0]'
[    1.952593] of_get_named_gpiod_flags: can't parse 'reset-gpio' property of node '/ocp/usb at 47400000/usb-phy at 47401b00[0]'
[    1.963876] am335x-phy-driver 47401b00.usb-phy: using lookup tables for GPIO lookup
[    1.971898] am335x-phy-driver 47401b00.usb-phy: lookup for GPIO reset failed
[    1.979262] am335x-phy-driver 47401b00.usb-phy: GPIO lookup for consumer vbus-detect
[    1.987368] am335x-phy-driver 47401b00.usb-phy: using device tree for GPIO lookup
[    1.995205] of_get_named_gpiod_flags: can't parse 'vbus-detect-gpios' property of node '/ocp/usb at 47400000/usb-phy at 47401b00[0]'
[    2.007133] of_get_named_gpiod_flags: can't parse 'vbus-detect-gpio' property of node '/ocp/usb at 47400000/usb-phy at 47401b00[0]'
[    2.018958] am335x-phy-driver 47401b00.usb-phy: using lookup tables for GPIO lookup
[    2.026983] am335x-phy-driver 47401b00.usb-phy: lookup for GPIO vbus-detect failed
[    2.034981] 47401b00.usb-phy supply vcc not found, using dummy regulator
[    2.045415] musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, bulk combine, bulk split, HB-ISO Rx, HB-ISO Tx, SoftConn)
[    2.056499] musb-hdrc: MHDRC RTL version 2.0 
[    2.061048] musb-hdrc: setup fifo_mode 4
[    2.065175] musb-hdrc: 28/31 max ep, 16384/16384 memory
[    2.070936] musb-hdrc musb-hdrc.1.auto: MUSB HDRC host driver
[    2.080720] musb-hdrc musb-hdrc.1.auto: new USB bus registered, assigned bus number 2
[    2.089811] usb usb2: New USB device found, idVendor=1d6b, idProduct=0002
[    2.096956] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[    2.104521] usb usb2: Product: MUSB HDRC host driver
[    2.109706] usb usb2: Manufacturer: Linux 4.0.0-rc7-00016-g7b43b47-dirty musb-hcd
[    2.117540] usb usb2: SerialNumber: musb-hdrc.1.auto
[    2.124711] hub 2-0:1.0: USB hub found
[    2.128756] hub 2-0:1.0: 1 port detected
[    2.137652] mousedev: PS/2 mouse device common for all mice
[    2.147011] input: ti-tsc as /devices/platform/ocp/44e0d000.tscadc/TI-am335x-tsc/input/input0
[    2.159357] omap_rtc 44e3e000.rtc: already running
[    2.166056] omap_rtc 44e3e000.rtc: rtc core: registered 44e3e000.rtc as rtc0
[    2.174300] i2c /dev entries driver
[    2.178022] Driver for 1-wire Dallas network protocol.
[    2.186852] omap_wdt: OMAP Watchdog Timer Rev 0x01: initial timeout 60 sec
[    2.195305] Driver 'mmcblk' needs updating - please use bus_type methods
[    2.203477] omap_hsmmc 48060000.mmc: GPIO lookup for consumer cd
[    2.209761] omap_hsmmc 48060000.mmc: using device tree for GPIO lookup
[    2.216657] of_get_named_gpiod_flags: can't parse 'cd-gpios' property of node '/ocp/mmc at 48060000[0]'
[    2.226223] of_get_named_gpiod_flags: can't parse 'cd-gpio' property of node '/ocp/mmc at 48060000[0]'
[    2.235740] omap_hsmmc 48060000.mmc: using lookup tables for GPIO lookup
[    2.242773] omap_hsmmc 48060000.mmc: lookup for GPIO cd failed
[    2.248873] omap_hsmmc 48060000.mmc: GPIO lookup for consumer wp
[    2.255167] omap_hsmmc 48060000.mmc: using device tree for GPIO lookup
[    2.262006] of_get_named_gpiod_flags: can't parse 'wp-gpios' property of node '/ocp/mmc at 48060000[0]'
[    2.271564] of_get_named_gpiod_flags: can't parse 'wp-gpio' property of node '/ocp/mmc at 48060000[0]'
[    2.281009] omap_hsmmc 48060000.mmc: using lookup tables for GPIO lookup
[    2.288030] omap_hsmmc 48060000.mmc: lookup for GPIO wp failed
[    2.332232] omap_hsmmc 481d8000.mmc: GPIO lookup for consumer cd
[    2.338525] omap_hsmmc 481d8000.mmc: using device tree for GPIO lookup
[    2.345420] of_get_named_gpiod_flags: can't parse 'cd-gpios' property of node '/ocp/mmc at 481d8000[0]'
[    2.354988] of_get_named_gpiod_flags: can't parse 'cd-gpio' property of node '/ocp/mmc at 481d8000[0]'
[    2.364456] omap_hsmmc 481d8000.mmc: using lookup tables for GPIO lookup
[    2.371458] omap_hsmmc 481d8000.mmc: lookup for GPIO cd failed
[    2.377577] omap_hsmmc 481d8000.mmc: GPIO lookup for consumer wp
[    2.383870] omap_hsmmc 481d8000.mmc: using device tree for GPIO lookup
[    2.390689] of_get_named_gpiod_flags: can't parse 'wp-gpios' property of node '/ocp/mmc at 481d8000[0]'
[    2.400248] of_get_named_gpiod_flags: can't parse 'wp-gpio' property of node '/ocp/mmc at 481d8000[0]'
[    2.409712] omap_hsmmc 481d8000.mmc: using lookup tables for GPIO lookup
[    2.416751] omap_hsmmc 481d8000.mmc: lookup for GPIO wp failed
[    2.462627] of_get_named_gpiod_flags: parsed 'gpios' property of node '/leds/led at 0[0]' - status (0)
[    2.473310] ledtrig-cpu: registered to indicate activity on CPUs
[    2.480119] usbcore: registered new interface driver usbhid
[    2.486056] usbhid: USB HID core driver
[    2.491721] oprofile: using arm/armv7
[    2.496361] TCP: cubic registered
[    2.499867] Initializing XFRM netlink socket
[    2.504577] NET: Registered protocol family 17
[    2.509299] NET: Registered protocol family 15
[    2.514002] can: controller area network core (rev 20120528 abi 9)
[    2.520614] NET: Registered protocol family 29
[    2.525393] can: raw protocol (rev 20120528)
[    2.529977] can: broadcast manager protocol (rev 20120528 t)
[    2.535965] can: netlink gateway (rev 20130117) max_hops=1
[    2.542166] Key type dns_resolver registered
[    2.546894] omap_voltage_late_init: Voltage driver support not added
[    2.553619] sr_dev_init: No voltage domain specified for smartreflex0. Cannot initialize
[    2.562108] sr_dev_init: No voltage domain specified for smartreflex1. Cannot initialize
[    2.571316] platform cpufreq-dt.0: Driver cpufreq-dt requests probe deferral
[    2.579506] ThumbEE CPU extension supported.
[    2.584079] Registering SWP/SWPB emulation handler
[    2.589096] SmartReflex Class3 initialized
[    2.594904] mmc0: MAN_BKOPS_EN bit is not set
[    2.605746] mmc0: new high speed MMC card at address 0001
[    2.614855] omap-gpmc 50000000.gpmc: GPMC revision 6.0
[    2.620417] gpmc_mem_init: disabling cs 0 mapped at 0x0-0x1000000
[    2.632159] mmcblk0: mmc0:0001 MMC04G 3.52 GiB 
[    2.637681] mmcblk0boot0: mmc0:0001 MMC04G partition 1 16.0 MiB
[    2.647490] 8000000.uart: ttyS0 at MMIO 0x8000000 (irq = 0, base_baud = 1152000) is a 16550A
[    2.658129] mmcblk0boot1: mmc0:0001 MMC04G partition 2 16.0 MiB
[    2.670556]  mmcblk0: p1
[    2.677387] 8000008.uart: ttyS1 at MMIO 0x8000008 (irq = 0, base_baud = 1152000) is a 16550A
[    2.711807] usb 2-1: new high-speed USB device number 2 using musb-hdrc
[    2.720331] tps65910 0-002d: No interrupt support, no core IRQ
[    2.734918] vrtc: supplied by vmain
[    2.742218] vio: supplied by vmain
[    2.749188] vdd_mpu: supplied by vmain
[    2.756594] vdd_core: supplied by vmain
[    2.765485] vdig1: supplied by vmain
[    2.772734] vdig2: supplied by vmain
[    2.779296] vpll: supplied by vmain
[    2.786243] vdac: supplied by vmain
[    2.792857] vaux1: supplied by vmain
[    2.799242] vaux2: supplied by vmain
[    2.805891] vaux33: supplied by vmain
[    2.812617] vmmc: supplied by vmain
[    2.819067] vbb: supplied by vmain
[    2.829270] si5351 0-0060: si5351_pll_recalc_rate - plla: p1 = 261632, p2 = 0, p3 = 1, parent_rate = 0, rate = 0
[    2.845198] si5351 0-0060: si5351_msynth_recalc_rate - ms0: p1 = 5632, p2 = 0, p3 = 1, m = 6144, parent_rate = 0, rate = 0
[    2.860877] si5351 0-0060: si5351_clkout_round_rate - clk0: rdiv = 1, parent_rate = 18432000, rate = 18432000
[    2.871292] si5351 0-0060: si5351_msynth_round_rate - ms0: a = 48, b = 0, c = 1, divby4 = 0, parent_rate = 884736000, rate = 18432000
[    2.883849] Division by zero in kernel.
[    2.887862] CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 4.0.0-rc7-00016-g7b43b47-dirty #11
[    2.896602] Hardware name: Generic AM33XX (Flattened Device Tree)
[    2.903008] Workqueue: deferwq deferred_probe_work_func
[    2.908505] [<c0015be4>] (unwind_backtrace) from [<c0012258>] (show_stack+0x10/0x14)
[    2.916631] [<c0012258>] (show_stack) from [<c066bbdc>] (dump_stack+0x84/0x9c)
[    2.924211] [<c066bbdc>] (dump_stack) from [<c031d8ec>] (Ldiv0+0x8/0x10)
[    2.931224] [<c031d8ec>] (Ldiv0) from [<c05704a0>] (si5351_pll_round_rate+0x3c/0x190)
[    2.939430] [<c05704a0>] (si5351_pll_round_rate) from [<c056caa8>] (clk_calc_new_rates+0x1dc/0x260)
[    2.948902] [<c056caa8>] (clk_calc_new_rates) from [<c056c9c8>] (clk_calc_new_rates+0xfc/0x260)
[    2.958005] Division by zero in kernel.
[    2.962030] CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 4.0.0-rc7-00016-g7b43b47-dirty #11
[    2.970748] Hardware name: Generic AM33XX (Flattened Device Tree)
[    2.977133] Workqueue: deferwq deferred_probe_work_func
[    2.982622] [<c0015be4>] (unwind_backtrace) from [<c0012258>] (show_stack+0x10/0x14)
[    2.990712] [<c0012258>] (show_stack) from [<c066bbdc>] (dump_stack+0x84/0x9c)
[    2.998279] [<c066bbdc>] (dump_stack) from [<c031d8ec>] (Ldiv0+0x8/0x10)
[    3.005312] [<c031d8ec>] (Ldiv0) from [<c031d8bc>] (__aeabi_uidivmod+0x8/0x18)
[    3.012879] [<c031d8bc>] (__aeabi_uidivmod) from [<c05704c8>] (si5351_pll_round_rate+0x64/0x190)
[    3.022078] [<c05704c8>] (si5351_pll_round_rate) from [<c056caa8>] (clk_calc_new_rates+0x1dc/0x260)
[    3.031560] [<c056caa8>] (clk_calc_new_rates) from [<c056c9c8>] (clk_calc_new_rates+0xfc/0x260)
[    3.040641] Division by zero in kernel.
[    3.044673] CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 4.0.0-rc7-00016-g7b43b47-dirty #11
[    3.053411] Hardware name: Generic AM33XX (Flattened Device Tree)
[    3.059776] Workqueue: deferwq deferred_probe_work_func
[    3.065265] [<c0015be4>] (unwind_backtrace) from [<c0012258>] (show_stack+0x10/0x14)
[    3.073382] [<c0012258>] (show_stack) from [<c066bbdc>] (dump_stack+0x84/0x9c)
[    3.080928] [<c066bbdc>] (dump_stack) from [<c031ce00>] (Ldiv0_64+0x8/0x18)
[    3.088225] [<c031ce00>] (Ldiv0_64) from [<c05704e0>] (si5351_pll_round_rate+0x7c/0x190)
[    3.096700] [<c05704e0>] (si5351_pll_round_rate) from [<c056caa8>] (clk_calc_new_rates+0x1dc/0x260)
[    3.106170] [<c056caa8>] (clk_calc_new_rates) from [<c056c9c8>] (clk_calc_new_rates+0xfc/0x260)
[    3.115280] si5351 0-0060: si5351_pll_round_rate - plla: a = 0, b = 0, c = 1, parent_rate = 0, rate = 0
[    3.125125] si5351 0-0060: si5351_msynth_recalc_rate - ms0: p1 = 5632, p2 = 0, p3 = 1, m = 6144, parent_rate = 0, rate = 0
[    3.137702] usb 2-1: New USB device found, idVendor=0424, idProduct=2512
[    3.144764] usb 2-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[    3.155260] hub 2-1:1.0: USB hub found
[    3.159354] hub 2-1:1.0: 2 ports detected
[    3.167784] si5351 0-0060: si5351_pll_set_rate - plla: p1 = 4294966784, p2 = 0, p3 = 1, parent_rate = 0, rate = 0
[    3.178577] si5351 0-0060: si5351_pll_recalc_rate - plla: p1 = 4294966784, p2 = 0, p3 = 1, parent_rate = 0, rate = 0
[    3.189999] si5351 0-0060: si5351_msynth_set_rate - ms0: p1 = 5632, p2 = 0, p3 = 1, divby4 = 0, parent_rate = 0, rate = 18432000
[    3.202118] si5351 0-0060: si5351_msynth_recalc_rate - ms0: p1 = 5632, p2 = 0, p3 = 1, m = 6144, parent_rate = 0, rate = 0
[    3.213686] si5351 0-0060: si5351_clkout_set_rate - clk0: rdiv = 128, parent_rate = 0, rate = 18432000
[    3.223696] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz
[    3.234369] cpufreq: __cpufreq_add_dev: CPU0: Running at unlisted freq: 1000000 KHz
[    3.291656] tilcdc 4830e000.lcdc: timeout waiting for framedone
[    3.331875] cpufreq: __cpufreq_add_dev: CPU0: Unlisted initial frequency changed to: 720000 KHz
[    3.401725] davinci_mdio 4a101000.mdio: davinci mdio revision 1.6
[    3.408133] davinci_mdio 4a101000.mdio: detected phy mask fffffffc
[    3.419351] libphy: 4a101000.mdio: probed
[    3.423725] davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver unknown
[    3.432182] davinci_mdio 4a101000.mdio: phy[1]: device 4a101000.mdio:01, driver unknown
[    3.442499] cpsw 4a100000.ethernet: Detected MACID = 6c:ec:eb:6c:8a:4b
[    3.453442] omap_rtc 44e3e000.rtc: setting system clock to 2015-02-26 04:13:35 UTC (1424924015)
[    3.462674] sr_init: No PMIC hook to init smartreflex
[    3.468302] sr_init: platform driver register failed for SR
[    3.538223] EXT4-fs (mmcblk0p1): mounted filesystem with ordered data mode. Opts: (null)
[    3.547109] VFS: Mounted root (ext4 filesystem) readonly on device 179:1.
[    3.558090] devtmpfs: mounted
[    3.562299] Freeing unused kernel memory: 444K (c0949000 - c09b8000)
INIT: version 2.88 booting
Starting udev
[    4.707396] udevd[88]: starting version 182
[   11.725776] EXT4-fs (mmcblk0p1): re-mounted. Opts: data=ordered
bootlogd: cannot allocate pseudo tty: No such file or directory
[   12.154807] random: dd urandom read with 53 bits of entropy available

ALSA: Restoring mixer settings... /usr/sbin/alsactl: load_state:1729: No soundcards found...
INIT: Entering runlevel: 5
Configuring network interfaces... done.
Starting system message bus: dbus.
Starting Network Interface Plugging Daemon: eth0.

[   16.740773] net eth0: initializing cpsw version 1.12 (0)
[   16.822202] net eth0: phy found : id is : 0x221513
[   16.827491] libphy: PHY 4a101000.mdio:02 not found
[   16.832620] net eth0: phy 4a101000.mdio:02 not found on slave 1
Starting OpenBSD Secure Shell server: sshd
[   16.961158] EXT4-fs (mmcblk0p1): warning: maximal mount count reached, running e2fsck is recommended
[   17.035196] EXT4-fs (mmcblk0p1): re-mounted. Opts: data=ordered
[   17.100834] EXT4-fs (mmcblk0p1): re-mounted. Opts: data=ordered

done.
Starting rpcbind daemon...rpcbind: cannot create socket for udp6
rpcbind: cannot create socket for tcp6
done.
creating NFS state directory: done
starting statd: done
Starting advanced power management daemon: No APM support in kernel (failed.)
Starting ntpd: done
Starting syslogd/klogd: done
Starting Lighttpd Web Server: lighttpd.

EMAC OpenEmbedded Linux - 5.0.0 - Beta Copyright (C) 2014, EMAC, Inc. All rights reserved.

Headless
som3517-som200

som3517-som200 login: [ 19.822835] cpsw 4a100000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
root
Password:
root at som3517-som200:~# cat /proc/version
Linux version 4.0.0-rc7-00016-g7b43b47-dirty (michael at deathray) (gcc version 4.9.1 (GCC) ) #11 SMP Tue Apr 14 18:51:01 CDT 2015 root at som3517-som200:~# cat /sys/kernel/debug/

bdi/                   extfrag/               kprobes/               musb-hdrc.0.auto/      omap_mux/              pwm                    sleep_time             ubifs/                 
clk/                   fault_around_bytes     memblock/              musb-hdrc.0.auto.dsps/ pinctrl/               regmap/                suspend_stats          usb/                   
dma_buf/               gpio                   mmc0/                  musb-hdrc.1.auto/      pm_debug/              regulator/             tracing/               wakeup_sources         
dri/                   hid/                   mmc1/                  musb-hdrc.1.auto.dsps/ pm_qos/                sched_features         ubi/                   
root at som3517-som200:~# cat /sys/kernel/debug/clk/
adc_tsc_fck/                clk_summary                 dpll_core_m4_ck/            dpll_per_ck/                gpio2_dbclk/                mmc_clk/                    stm_clk_div_ck/             timer7_fck/
aes0_fck/                   clkdiv32k_ck/               dpll_core_m4_div2_ck/       dpll_per_m2_ck/             gpio3_dbclk/                mmu_fck/                    stm_pmd_clock_mux_ck/       trace_clk_div_ck/
cefuse_fck/                 clkdiv32k_ick/              dpll_core_m5_ck/            dpll_per_m2_div4_ck/        ieee5000_fck/               ms0/                        sys_clkin_ck/               trace_pmd_clk_mux_ck/
clk0/                       clkout2_ck/                 dpll_core_m6_ck/            dpll_per_m2_div4_wkupdm_ck/ l3_gclk/                    ms1/                        sysclk_div_ck/              usbotg_fck/
clk1/                       clkout2_div_ck/             dpll_core_x2_ck/            ehrpwm0_tbclk/              l3s_gclk/                   ms2/                        sysclkout_pre_ck/           virt_19200000_ck/
clk2/                       cpsw_125mhz_gclk/           dpll_ddr_ck/                ehrpwm1_tbclk/              l4_rtc_gclk/                plla/                       tclkin_ck/                  virt_24000000_ck/
clk_24mhz/                  cpsw_cpts_rft_clk/          dpll_ddr_m2_ck/             ehrpwm2_tbclk/              l4fw_gclk/                  pllb/                       timer1_fck/                 virt_25000000_ck/
clk_32768_ck/               dbg_clka_ck/                dpll_ddr_m2_div2_ck/        gfx_fck_div_ck/             l4hs_gclk/                  pruss_ocp_gclk/             timer2_fck/                 virt_26000000_ck/
clk_dump                    dbg_sysclk_ck/              dpll_disp_ck/               gfx_fclk_clksel_ck/         l4ls_gclk/                  rng_fck/                    timer3_fck/                 wdt1_fck/
clk_orphan_dump             dcan0_fck/                  dpll_disp_m2_ck/            gpio0_dbclk/                lcd_gclk/                   sha0_fck/                   timer4_fck/                 xtal/
clk_orphan_summary          dcan1_fck/                  dpll_mpu_ck/                gpio0_dbclk_mux_ck/         mcasp0_fck/                 smartreflex0_fck/           timer5_fck/                 
clk_rc32k_ck/               dpll_core_ck/               dpll_mpu_m2_ck/             gpio1_dbclk/                mcasp1_fck/                 smartreflex1_fck/           timer6_fck/                 
root at som3517-som200:~# cat /sys/kernel/debug/clk/clk_summary 
   clock                         enable_cnt  prepare_cnt        rate   accuracy   phase
----------------------------------------------------------------------------------------
 tclkin_ck                                0            0    12000000          0 0  
 virt_26000000_ck                         1            1    26000000          0 0  
    sys_clkin_ck                         11           23    26000000          0 0  
       timer6_fck                         0            1    26000000          0 0  
       timer3_fck                         0            1    26000000          0 0  
       dbg_sysclk_ck                      0            1    26000000          0 0  
       timer7_fck                         0            1    26000000          0 0  
       timer5_fck                         0            1    26000000          0 0  
       timer4_fck                         0            1    26000000          0 0  
       timer2_fck                         1            1    26000000          0 0  
       timer1_fck                         1            1    26000000          0 0  
       cefuse_fck                         0            0    26000000          0 0  
       dpll_per_ck                        2            2   960000000          0 0  
          usbotg_fck                      1            1   960000000          0 0  
          dpll_per_m2_ck                  3            4   192000000          0 0  
             mmc_clk                      0            3    96000000          0 0  
             clk_24mhz                    1            1    24000000          0 0  
                clkdiv32k_ck              1            1       32786          0 0  
                   clkdiv32k_ick           1            5       32786          0 0  
                      wdt1_fck            0            1       32786          0 0  
                      gpio3_dbclk           0            1       32786          0 0  
                      gpio2_dbclk           0            1       32786          0 0  
                      gpio1_dbclk           0            1       32786          0 0  
             dpll_per_m2_div4_ck           1            9    48000000          0 0  
             dpll_per_m2_div4_wkupdm_ck           1            2    48000000          0 0  
       dpll_disp_ck                       1            1    18000000          0 0  
          dpll_disp_m2_ck                 1            1    18000000          0 0  
             lcd_gclk                     1            1    18000000          0 0  
       dpll_ddr_ck                        1            1   400000000          0 0  
          dpll_ddr_m2_ck                  2            2   400000000          0 0  
             dpll_ddr_m2_div2_ck           1            1   200000000          0 0  
       dpll_mpu_ck                        1            1   275000000          0 0  
          dpll_mpu_m2_ck                  4            4   275000000          0 0  
       dpll_core_ck                       1            1  1000000000          0 0  
          dpll_core_x2_ck                 2            2  2000000000          0 0  
             dpll_core_m6_ck              0            0   500000000          0 0  
             dpll_core_m5_ck              1            1   250000000          0 0  
                cpsw_cpts_rft_clk           0            0   250000000          0 0  
                cpsw_125mhz_gclk           3            3   125000000          0 0  
             dpll_core_m4_ck              9           11   200000000          0 0  
                dbg_clka_ck               0            2   200000000          0 0  
                   trace_pmd_clk_mux_ck           0            1   200000000          0 0  
                      trace_clk_div_ck           0            1    50000000          0 0  
                   stm_pmd_clock_mux_ck           0            0   200000000          0 0  
                      stm_clk_div_ck           0            0    50000000          0 0  
                gfx_fclk_clksel_ck           0            1   200000000          0 0  
                   gfx_fck_div_ck           0            1   200000000          0 0  
                sysclk_div_ck             0            0   200000000          0 0  
                l4hs_gclk                 2            2   200000000          0 0  
                l4_rtc_gclk               0            0   100000000          0 0  
                dpll_core_m4_div2_ck          15           17   100000000          0 0  
                   l4ls_gclk             45           60   100000000          0 0  
                      ehrpwm2_tbclk           0            1   100000000          0 0  
                      ehrpwm1_tbclk           0            0   100000000          0 0  
                      ehrpwm0_tbclk           0            0   100000000          0 0  
                   l4fw_gclk              1            1   100000000          0 0  
                   l3s_gclk              10           10   100000000          0 0  
                   ieee5000_fck           0            0   100000000          0 0  
                mmu_fck                   0            0   200000000          0 0  
                l3_gclk                  13           15   200000000          0 0  
                   pruss_ocp_gclk           0            1   200000000          0 0  
       rng_fck                            2            2    26000000          0 0  
       aes0_fck                           1            2    26000000          0 0  
       sha0_fck                           1            1    26000000          0 0  
       smartreflex1_fck                   0            1    26000000          0 0  
       smartreflex0_fck                   0            1    26000000          0 0  
       mcasp1_fck                         0            1    26000000          0 0  
       mcasp0_fck                         0            1    26000000          0 0  
       dcan1_fck                          0            1    26000000          0 0  
       dcan0_fck                          0            1    26000000          0 0  
       adc_tsc_fck                        1            1    26000000          0 0  
 virt_25000000_ck                         0            0    25000000          0 0  
 virt_24000000_ck                         0            0    24000000          0 0  
 virt_19200000_ck                         0            0    19200000          0 0  
 clk_rc32k_ck                             0            1       32000          0 0  
    gpio0_dbclk_mux_ck                    0            1       32000          0 0  
       gpio0_dbclk                        0            1       32000          0 0  
 clk_32768_ck                             2            2       32768          0 0  
    sysclkout_pre_ck                      1            1       32768          0 0  
       clkout2_div_ck                     1            1       32768          0 0  
          clkout2_ck                      1            1       32768          0 0  
 xtal                                     0            0           0          0 0  
    pllb                                  0            0           0          0 0  
       ms2                                0            0           0          0 0  
          clk2                            0            0           0          0 0  
       ms1                                0            0           0          0 0  
          clk1                            0            0           0          0 0  
    plla                                  0            0           0          0 0  
       ms0                                0            0           0          0 0  
          clk0                            0            0           0          0 0 

I see a bug in your dt data.

<snip>

+ clocks {
+ ref27: ref27 {
+ #clock-cells = <0>;
+ compatibale = "fixed-clock";

This should be compatible, right? DT is annoying in that it doesn't verify property names.

+ clock-frequency = <27000000>;
+ };
+ };

-Tero

Ooops.

Now the clock appears in /sys/kernel/debug/clk:
root at som3517-som200:/sys/kernel/debug/clk# cat clk_summary
clock enable_cnt prepare_cnt rate accuracy phase
----------------------------------------------------------------------------------------
ref27 0 0 27000000 0 0
...

There is still an issue with the si5351.

I had to comment out the clk_put here for the frequency to show up:
http://lxr.free-electrons.com/source/drivers/clk/clk-si5351.c#L1133

Ideas?

What is the most recent upstream commit that you are based on?

Regards,
Mike

I am working from 4.0.0-rc7.

7b43b47373d40d557cd7e1a84a0bd8ebc4d745ab

Hmm, I wonder why si5351 calls clk_put immediately after of_clk_get in the first place, as far as I understand this destroys the clock handle, which is still being used later in the code.

-Tero

Not sure how this ever worked. This has been in the code since the initial commit.

Sebastian?

[...]

The reason it worked before may be related with recent rework of clk_put() itself and clk cookies instead of pointers. I lost track on the recent clk subsystem changes here, sorry.

However, droping the clk immediately surely isn't right. The thing is, we can remove the clk_put() just because there is no _remove() for that driver. I remember that back in the days the driver was mainlined, clk removal wasn't too easy.

FWIW, as soon as _remove() support will be added by someone, we'll have to rethink passing struct clk* by platform_data or at least double-check if we ever used [of_]clk_get() to obtain it.

Mind to send a patch removing the clk_put() on !IS_ERR and add a proper error path instead? While of_clk_get() is the only calls that need cleanup on error in si5351_dt_parse() we should probably move that calls to the end of this function. Otherwise we'd also have to cleanup on every of_parse_foo() failure.

Sebastian

What would be the proper error path?
What cleanup is required?

It should be noted that there are more deep rooted issues with the driver that I have noticed. For one the driver behaves differently if the debugging is on and when it is off.

Here is what the kernel reports with debugging off:
root at som3517-som200:~# cat /sys/kernel/debug/clk/clk_summary
clock enable_cnt prepare_cnt rate accuracy phase
----------------------------------------------------------------------------------------

 ref27                                    0            0    27000000          0 0  
    xtal                                  0            0    27000000          0 0  
       pllb                               0            0   599999994          0 0  
          ms0                             0            0    12499999          0 0  
             clk0                         0            0    12499999          0 0  
       plla                               0            0   599999994          0 0  
          ms2                             0            0     8219178          0 0  
             clk2                         0            0     8219178          0 0  
          ms1                             0            0    94117646          0 0  
             clk1                         0            0    94117646          0 0  

Here is what the kernel reports with debugging on:
clock enable_cnt prepare_cnt rate accuracy phase
----------------------------------------------------------------------------------------

 ref27                                    0            0    27000000          0 0  
    xtal                                  0            0    27000000          0 0  
       pllb                               0            0   884736000          0 0  
          ms0                             0            0    18432000          0 0  
             clk0                         0            0    18432000          0 0  
       plla                               0            0   897023997          0 0  
          ms2                             0            0    12287999          0 0  
             clk2                         0            0    12287999          0 0  
          ms1                             0            0   140709646          0 0  
             clk1                         0            0   140709646          0 0 

Note this is with the following devicetree entry:

        si5351: clock-generator {
                #address-cells = <1>;
                #size-cells = <0>;
                #clock-cells = <1>;
                compatible = "silabs,si5351a-msop";
                reg = <0x60>;
                status = "okay";

                /* connect xtal input to 27MHz reference */
                clocks = <&ref27>;

                /* connect xtal input as source of pll0 and pll1 */
                silabs,pll-source = <0 0>, <1 0>;

                clkout0: clkout0 {
                        reg = <0>;
                        silabs,drive-strength = <8>;
                        silabs,multisynth-source = <1>;
                        silabs,clock-source = <0>;
                        silabs,pll-master;
                        clock-frequency = <18432000>;
                 };

                clkout1: clkout1 {
                        reg = <1>;
                        silabs,drive-strength = <8>;
                        silabs,multisynth-source = <0>;
                        silabs,clock-source = <0>;
                        clock-frequency = <8000000>;
                };

                clkout2: clkout2 {
                        reg = <2>;
                        silabs,drive-strength = <8>;
                        silabs,multisynth-source = <0>;
                        silabs,clock-source = <0>;
                        silabs,pll-master;
                        clock-frequency = <12288000>;
                };
        };

I am losing hope that this driver is stable enough to even use in production.

A proper error path would be to release any claimed resource on any error. If you look at the code, the only resources that need to be released are the two clocks in question.

I guess you mean #define DEBUG in the driver?

Do you have any measurement equipment to check what is actually set?

Is this what you expect for clk0?

ditto for clk2?

This is wrong, I agree. Looks like round_rate()/recalc_rate() of msynth or clkout is broken with respect to non-pll-master clocks.

I had a quick look at drivers/clk.c too, there has been a lot of churn in clk API since I last booted my device using si5351.

Is there any way to try out a less recent kernel, let's say two or three releases before 4.0?

We should just confirm that there has been an issue with it before already.

I have no clue about the debug on/off issue at the moment.

Who said it is stable for production use? The driver is written from scratch based on _very_ limited information of the datasheet an appnote. Also, I only have a single setup with si5351, that is no way enough to test every combination.

I never heard serious complaints before, so either you help improving this driver or better ask SiLabs for a table-based driver for your specific setup.

Sebastian

So for every error return in the probe function and in the of si5351_dt_parse it needs to clk_put first right?

See attached patch to see if we are on the same page.

Yes.

Yes, I have an oscilloscope here at my desk.
The reported numbers do not always correspond to the actual output in some cases.

The ms2 output has appeared to stop working all together sometime whilest testing. I may have to solder a new chip on there.

Could misconfiguration damage the chip?

Yes.

Yes.

Could you provide a specific version that you think has the best chances of working?

Well it is not in staging and I am sure it took much work to get it working for you.

I have routines to program the chip from U-Boot and Linux userspace using the table method. I was hoping that a mainline driver could replace these hackish utilities.

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non-staging doesn't mean code is absolutely bug free. Linux kernel is still just software, and as we know, every piece of software has bugs (except maybe the simplest hello-world app.)

You can still replace your hack solution.

The beauty of linux comes in that if you find a bug someplace, you can just fix it, post a patch upstream, and get it fixed for good. :)

-Tero

[...]

Not quite. The driver should clk_put() every clock that it called a [of_]clk_get() for. The thing is that clocks can be passed by platform_data and we never claim them.

Adding a .remove() function needs more care because of the pdata passed clocks. I admit that back when the driver was introduced clk_put() wasn't really necessary at all.

[...]

is "not always correspond" close or way off the requested frequency?

Stability is an issue that I am aware of. Neither the datasheet nor the appnote were clear about any order the clocks should be set or how long we should wait between changing pll/ms/clkout parameters.

SiLabs suggests to configure all clocks at once and never change them later, at least that is what you can read from the public documents. The drivers you mention below can however reveal some steps that have to be taken care of before and after changing parameters.

You should know that a lot of things can damage a chip and misconfiguration is among them, yes. I cannot tell if that is the cause though.

[...]

My guess with 2-3 releases before 4.0 was because somewhere in between clk API must have switched from passing struct clk pointers to clk cookies.

[...]

From your patch (that you should inline next time please):

@@ -1129,11 +1130,21 @@ static int si5351_dt_parse(struct i2c_client *client,
return -ENOMEM;

pdata->clk_xtal = of_clk_get(np, 0);
- if (!IS_ERR(pdata->clk_xtal))
- clk_put(pdata->clk_xtal);
- pdata->clk_clkin = of_clk_get(np, 1);
- if (!IS_ERR(pdata->clk_clkin))
- clk_put(pdata->clk_clkin);
+ if (IS_ERR(pdata->clk_xtal)) {
+ dev_err(&client->dev,
+ "xtal clock not speficied\n");
+ return -ENODEV;
+ }
+
+ if (variant == SI5351_VARIANT_C) {
+ pdata->clk_clkin = of_clk_get(np, 1);
+ if (IS_ERR(pdata->clk_clkin)) {
+ dev_err(&client->dev,
+ "clkin clock not speficied\n");
+ ret = -ENODEV;
+ goto err_put_clk_of;
+ }
+ }

Basically, yes. But as I said, if you move that to the end of si5351_dt_parse() you won't have to add

@ -1143,14 +1154,16 @@ static int si5351_dt_parse(struct i2c_client *client,
if (num >= 2) {
dev_err(&client->dev,
"invalid pll %d on pll-source prop\n", num);
- return -EINVAL;
+ ret = -EINVAL;
+ goto err_put_clk_of;
}

this to each of the sanity checks. Claiming the clock resources at the end saves you from tearing down the resources on each error above.

Another thing is that you now require VARIANT_C devices to always pass both, xtal and clkin. I can live with it until we find somebody who actually uses C-type devices with only one clock input connected.

Adding a .remove() function to si5351 definitely needs more care with respect to claimed and pdata passed clocks. I am not sure we should go for it before we haven't ruled out the other issues.

Sebastian

I've always said clocks (as in struct clk) should never be passed through platform data.

FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.

Should the ones from the platform data be claimed?

Is it necessary now?

Both.

The drivers were not provided we wrote them and they do nothing but write the registers with the raw values provided from the SiLab clock generator software.

Well I did something to the chip.

Sure I can move it down put it seems counterintuitive to parse parameters that rely on the clocks before they are determined to be specified.

Okay I did not realize that the C variant could run with one or the other.

Okay. Either way we should probably open a new thread because this is not an issue with the processor support. Let me know how you want to proceed.

It looks like this chip is used on the dove-cubox:
http://lxr.free-electrons.com/source/arch/arm/boot/dts/dove-cubox.dts#L77

I wonder if this issue effects that board as well.

Any one out there want with one of these board want to test it?

It looks like the clock is used for a audio master clock so it may sound pretty funny when playing audio. :)

What is the alternative for systems that still use the old platform files?

Hypothetically speaking of course.

clkdev, which has pre-existed DT.

FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.

Quoting Russell King - ARM Linux (2015-04-17 03:18:33)

+1

And for ccf clock drivers Stephen and I plan to change the behavior of clk_register() at some point so that it returns an error code and not a struct clk. This will make clk_dev the only way to get at a struct clk for users of the ccf implementation.

Of course it is still possible to clk_get from some place and pass as platform_data, but every little bit helps.

Regards,
Mike