Question regarding suspend/resume

Is there any reference how to decode the output of /debug/pm_debug/count? I'm trying to figure out when I resume why it says the core_pwrdm didn't enter the target state, and I'm assuming because a clock used is not disabled in the suspend path, but as fars as I can tell there's no output in the pm_debug code that tells which clocks in a power domain are active at the time of a suspend.

Any ideas?

Peter Barada
[email protected]

You're right.

What you need the patch in my pm-wip/debug branch from my pm tree[1]. With that patch, it takes a snapshot of the PRCM registers just before and after suspend.

When you come back from suspend, view the register snapshot just before suspend:

# cat /debug/pm_debug/register/1  

and the register snapshot just after

# cat /debug/pm_debug/register/2

the snapshot just before suspend is useful for debugging problems like yours, and the snapshot just after can be useful for debugging wakeups.

Feel free to post the register dump if you want some help deciphering it. If you do, please post more details on what kernel you're using as well as the bootloader etc.

One of the common root causes for a problem like yours is a bootloader that leaves a particular module in a state that it cannot properly idle. If the kernel is not using that particular device and/or has not reset that device, the result is the powerdomain for that device can not hit idle and you'll have a problem like yours.

Kevin

[1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git

Kevin,

Thanks for helping me to understand things.

The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1] with their u-boot [2] and x-loader[3], modified to run on Logic's DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP). I've added to this kernel a stripped board file (stripped from board-omap3evm.c) that supplies enough to bring up the mmc and serial ports - platform code registers other devices. Its built with omap3_evm_defconfig with the addition of my MACH_DM3730_SOM_LV/TORPEDO machine description (which causes my board-dm3730logic.c minimal board file to be compiled in):

/*
* linux/arch/arm/mach-omap2/board-dm3730logic.c
*
* Copyright (C) 2011 Logic Product Development
*
* Modified from mach-omap2/board-omap3evm.c
*
* Initial code: Syed Mohammed Khasim
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/gpio.h>
#include <linux/input.h>
#include <linux/interrupt.h>

#include <linux/i2c/twl.h>

#include <linux/regulator/fixed.h>
#include <linux/regulator/machine.h>
#include <linux/mmc/host.h>

#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>

#include <plat/board.h>
#include <plat/usb.h>
#include <plat/common.h>

#include "mux.h"
#include "sdram-micron-mt29c4g48mazapakq-5.h"
#include "mmc-twl4030.h"
#include "pm.h"
#include "prm-regbits-34xx.h"
#include "omap3-opp.h"

static struct twl4030_hsmmc_info mmc[] = {
{
.mmc = 1,
.wires = 4,
.gpio_cd = -EINVAL,
.gpio_wp = -EINVAL,
},
{} /* Terminator */
};

static struct regulator_consumer_supply dm3730logic_vmmc1_supply = {
.supply = "vmmc",
};

static int dm3730logic_twl_gpio_setup(struct device *dev,
unsigned gpio, unsigned ngpio)

{
    twl4030_mmc_init(mmc);

    /* link regulator to MMC adapter */
    dm3730logic_vmmc1_supply.dev = mmc[0].dev;

    return 0;
}

static struct twl4030_gpio_platform_data dm3730logic_gpio_data = {
.gpio_base = OMAP_MAX_GPIO_LINES,
.irq_base = TWL4030_GPIO_IRQ_BASE,
.irq_end = TWL4030_GPIO_IRQ_END,
.use_leds = true,
.setup = dm3730logic_twl_gpio_setup,
};

/* VMMC1 for MMC1 pins CMD, CLK, DAT0..DAT3 (20 mA, plus card == max 220 mA) */ static struct regulator_init_data dm3730logic_vmmc1 = {
.constraints = {
.min_uV = 1850000,
.max_uV = 3150000,
.valid_modes_mask = REGULATOR_MODE_NORMAL
| REGULATOR_MODE_STANDBY,
.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE
| REGULATOR_CHANGE_MODE
| REGULATOR_CHANGE_STATUS,
},
.num_consumer_supplies = 1,
.consumer_supplies = &dm3730logic_vmmc1_supply,
};

static struct twl4030_platform_data dm3730logic_twldata = {
    .irq_base    = TWL4030_IRQ_BASE,
    .irq_end    = TWL4030_IRQ_END,

    .gpio        = &dm3730logic_gpio_data,

    /* platform_data for children goes here */
    .vmmc1        = &dm3730logic_vmmc1,
};

static struct i2c_board_info __initdata dm3730logic_i2c_boardinfo[] = {
    {
        I2C_BOARD_INFO("twl4030", 0x48),
        .flags = I2C_CLIENT_WAKE,
        .irq = INT_34XX_SYS_NIRQ,
        .platform_data = &dm3730logic_twldata,
    },
};

static int __init dm3730logic_i2c_init(void)

{
    omap_register_i2c_bus(1, 2600, dm3730logic_i2c_boardinfo,
            ARRAY_SIZE(dm3730logic_i2c_boardinfo));
    return 0;
}

#ifdef CONFIG_OMAP_MUX
static struct omap_board_mux board_mux[] __initdata = {
{ .reg_offset = OMAP_MUX_TERMINATOR },
};
#endif

static struct omap_board_config_kernel dm3730logic_config[] __initdata = { };

static struct omap_opp * _omap37x_mpu_rate_table = omap37x_mpu_rate_table;
static struct omap_opp * _omap37x_dsp_rate_table = omap37x_dsp_rate_table;
static struct omap_opp * _omap37x_l3_rate_table = omap37x_l3_rate_table;

static void __init dm3730logic_init_irq(void)
{

    omap_board_config = dm3730logic_config;
    omap_board_config_size = ARRAY_SIZE(dm3730logic_config);
    omap2_init_common_hw(mt29c4g48mazapakq5_sdrc_params,
            NULL,
            _omap37x_mpu_rate_table,
            _omap37x_dsp_rate_table,
            _omap37x_l3_rate_table);

    omap_init_irq();
    omap_gpio_init();
}

static struct platform_device *dm3730logic_devices[] __initdata = { };

static void __init dm3730logic_init(void)

{
    omap3_mux_init(board_mux, OMAP_PACKAGE_CBP);
    dm3730logic_i2c_init();
    platform_add_devices(dm3730logic_devices,
            ARRAY_SIZE(dm3730logic_devices));
    omap_serial_init();
}

static void __init dm3730logic_map_io(void)

{
    omap2_set_globals_343x();
    omap2_map_common_io();
}

MACHINE_START(DM3730_SOM_LV, "DM3730 SOM LV")

    /* Maintainer: Peter Barada - Logic Product Development */
    .phys_io    = 0x48000000,
    .io_pg_offst    = ((0xfa000000) >> 18) & 0xfffc,
    .boot_params    = 0x80000100,
    .map_io        = dm3730logic_map_io,
    .init_irq    = dm3730logic_init_irq,
    .init_machine    = dm3730logic_init,
    .timer        = &omap_timer,

MACHINE_END

MACHINE_START(DM3730_TORPEDO, "DM3730 Torpedo")

    /* Maintainer: Peter Barada - Logic Product Development */
    .phys_io    = 0x48000000,
    .io_pg_offst    = ((0xfa000000) >> 18) & 0xfffc,
    .boot_params    = 0x80000100,
    .map_io        = dm3730logic_map_io,
    .init_irq    = dm3730logic_init_irq,
    .init_machine    = dm3730logic_init,
    .timer        = &omap_timer,

MACHINE_END

I've verified this kernel boots up (off an SD card) and goes fully into suspend on a DM3730EVM, but when booted on my board(s) shows the following (/debug/pm_debug/register output follow):

[root@arago /]# echo mem > /sys/power/state
PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done. Suspending console(s) (use no_console_suspend to debug)
mmc0: card 0007 removed
Powerdomain (core_pwrdm) didn't enter target state 1
Could not enter target state in pm_suspend
Restarting tasks ... done.
[root@arago /]# mmc0: host does not support reading read-only switch. assuming write-enable.
mmc0: new high speed SD card at address 0007
mmcblk0: mmc0:0007 SD512 485 MiB
mmcblk0: p1
[root@arago /]# mkdir /debug
[root@arago /]# mount -t debugfs debug /debug
[root@arago /]# cat /debug/pm_debug/registers/1
MOD: CM_IVA2 (48014000)
04 => 00000017 20 => 00000001 34 => 00000001 40 => 00080a00
44 => 00000001 48 => 00000003
MOD: CM_OCP (48004800)
00 => 00000010 10 => 00000001
MOD: CM_MPU (48004900)

  04 => 00000037  24 => 00000001  34 => 00000001  40 => 00112c0c
  44 => 00000001  48 => 00000003  4c => 00000001
MOD: CM_CORE (48004a00)
  10 => 00000042  20 => ffffffbd  24 => 0000001f  28 => 0000000d
  30 => fffffed9  34 => 0000001f  38 => 0000000c  40 => 0000130a
  48 => 0000003f  4c => 00000003

MOD: CM_SGX (48004b00)
20 => 00000001 40 => 00000005 48 => 00000003
MOD: CM_WKUP (48004c00)
00 => 00000001 10 => 0000000d 20 => 000002f2 30 => 0000003f 40 => 00000014
MOD: CM_CCR (48004d00)

  00 => f8311007  04 => 00000011  20 => 00000001  30 => 00000009
  34 => 00000001  40 => 08c80c00  44 => 0481b00c  48 => 00000009
  4c => 00003c0c  50 => 00000001  70 => 00000003

MOD: CM_DSS (48004e00)
20 => 00000003 30 => 00000001 40 => 00001009 48 => 00000003
MOD: CM_CAM (48004f00)
20 => 00000001 30 => 00000001 40 => 00000004 48 => 00000003
MOD: CM_PER (48005000)

  10 => 0003e000  20 => 00041fff  30 => 0003ffff  40 => 000000ff
  44 => 00000006  48 => 00000003  4c => 00000001

MOD: CM_EMU (48005100)
40 => 03020a50 48 => 00000001
MOD: CM_NEON (48005300)
48 => 00000003
MOD: CM_USB (48005400)
20 => 00000003 30 => 00000001 48 => 00000003
MOD: PRM_IVA2 (48316000)
50 => 00000007 e0 => 00ff0f05 e4 => 00000555 e8 => 00000555
MOD: PRM_OCP (48306800)
04 => 00000010 14 => 00000001 1c => 00000201
MOD: PRM_MPU (48306900)
d4 => 00000012 e0 => 00030105 e4 => 000000c7 e8 => 000000c7
MOD: PRM_CORE (48306a00)

  58 => 00000300  a0 => c33ffe18  a4 => c33ffe18  e0 => 000f0315
  e4 => 000000f7  e8 => 000000f7  f0 => 00000004  f8 => 00000004

MOD: PRM_SGX (48306b00)
e0 => 00030104
MOD: PRM_WKUP (48306c00)
a0 => 0001010b a4 => 0000010b b0 => 00010000
MOD: PRM_CCR (48306d00)
40 => 00000003
MOD: PRM_DSS (48306e00)
a0 => 00000001 e0 => 00030105 e4 => 00000001 e8 => 00000001
MOD: PRM_CAM (48306f00)
58 => 00000001 e0 => 00030105 e4 => 00000001 e8 => 00000001
MOD: PRM_PER (48307000)
a0 => 0003e807 a4 => 0003e807 c8 => 00000007 e0 => 00030105 e4 => 00000007 e8 => 00000007
MOD: PRM_EMU (48307100)
e4 => 00000100
MOD: PRM_GLBL (48307200)

  20 => 00120012  24 => 00010000  2c => 28201e00  30 => 2b201e00
  34 => 00120000  38 => 00000008  54 => 00001006  58 => 00000001
  60 => 00000002  64 => 00000050  70 => 00000048  90 => 0fff0fff
  94 => 000000ff  98 => 000000ff  9c => 00000002  a0 => 000000ff
  b0 => 00202808  b4 => 0001f401  b8 => 0001f404  bc => 4000ffff
  c0 => 00000028  c4 => 00000001  d0 => 00202b08  d4 => 0001f401
  d8 => 0001f404  dc => 2c00ffff  e0 => 0000002b  e4 => 00000001

MOD: PRM_NEON (48307300)
c8 => 00000002 e0 => 00000005 e4 => 00000003 e8 => 00000003
MOD: PRM_USB (48307400)
a0 => 00000001 a4 => 00000001 a8 => 00000001 e0 => 00030115 e4 => 00000001 e8 => 00000001

[root@arago /]# cat /debug/pm_debug/registers/2
MOD: CM_IVA2 (48014000)
04 => 00000017 20 => 00000001 34 => 00000001 40 => 00080a00 44 => 00000001 48 => 00000003
MOD: CM_OCP (48004800)
00 => 00000010 10 => 00000001
MOD: CM_MPU (48004900)

  04 => 00000037  24 => 00000001  34 => 00000001  40 => 00112c0c
  44 => 00000001  48 => 00000003  4c => 00000001
MOD: CM_CORE (48004a00)
  10 => 00000042  20 => ffffffbd  24 => 0000001f  28 => 0000000d
  30 => fffffed9  34 => 0000001f  38 => 0000000c  40 => 0000130a
  48 => 0000003f  4c => 00000003

MOD: CM_SGX (48004b00)
20 => 00000001 40 => 00000005 48 => 00000003
MOD: CM_WKUP (48004c00)
00 => 00000001 10 => 0000000d 20 => 000002f2 30 => 0000003f 40 => 00000014
MOD: CM_CCR (48004d00)

  00 => f8311007  04 => 00000011  20 => 00000001  30 => 00000009
  34 => 00000001  40 => 08c80c00  44 => 0481b00c  48 => 00000009
  4c => 00003c0c  50 => 00000001  70 => 00000003

MOD: CM_DSS (48004e00)
20 => 00000003 30 => 00000001 40 => 00001009 48 => 00000003
MOD: CM_CAM (48004f00)
20 => 00000001 30 => 00000001 40 => 00000004 48 => 00000003
MOD: CM_PER (48005000)

  10 => 0003e000  20 => 00041fff  30 => 0003ffff  40 => 000000ff
  44 => 00000006  48 => 00000003  4c => 00000001

MOD: CM_EMU (48005100)
40 => 03020a50 48 => 00000001
MOD: CM_NEON (48005300)
48 => 00000003
MOD: CM_USB (48005400)
20 => 00000003 30 => 00000001 48 => 00000003
MOD: PRM_IVA2 (48316000)
50 => 00000007 e0 => 00ff0f05 e4 => 00000555 e8 => 00000555
MOD: PRM_OCP (48306800)
04 => 00000010 14 => 00000001 18 => 00000201 1c => 00000201
MOD: PRM_MPU (48306900)
d4 => 00000012 e0 => 00030105 e4 => 000000c7 e8 => 00000045
MOD: PRM_CORE (48306a00)

  58 => 00000300  a0 => c33ffe18  a4 => c33ffe18  b0 => 00002000
  e0 => 000f0315  e4 => 000000f7  e8 => 000000f7  f0 => 00000004

f8 => 00000004
MOD: PRM_SGX (48306b00)
e0 => 00030104
MOD: PRM_WKUP (48306c00)
a0 => 0001010b a4 => 0000010b b0 => 00010100
MOD: PRM_CCR (48306d00)
40 => 00000003
MOD: PRM_DSS (48306e00)
a0 => 00000001 e0 => 00030105 e4 => 00000001 e8 => 00000001
MOD: PRM_CAM (48306f00)
58 => 00000001 e0 => 00030105 e4 => 00000001 e8 => 00000001
MOD: PRM_PER (48307000)
a0 => 0003e807 a4 => 0003e807 c8 => 00000007 e0 => 00030105 e4 => 00000007 e8 => 00000005
MOD: PRM_EMU (48307100)
e4 => 00000100
MOD: PRM_GLBL (48307200)

  20 => 00120012  24 => 00010000  2c => 28201e00  30 => 2b201e00
  34 => 00120000  38 => 00000008  54 => 00001006  58 => 00000001
  60 => 00000002  64 => 00000050  70 => 00000048  90 => 0fff0fff
  94 => 000000ff  98 => 000000ff  9c => 00000002  a0 => 000000ff
  b0 => 00202808  b4 => 0001f401  b8 => 0001f404  bc => 4000ffff
  c0 => 00000028  c4 => 00000001  d0 => 00202b08  d4 => 0001f401
  d8 => 0001f404  dc => 2c00ffff  e0 => 0000002b  e4 => 00000001

MOD: PRM_NEON (48307300)
c8 => 00000002 e0 => 00000005 e4 => 00000003 e8 => 00000001
MOD: PRM_USB (48307400)
a0 => 00000001 a4 => 00000001 a8 => 00000001 e0 => 00030115 e4 => 00000001 e8 => 00000001
[root@arago /]#

Any help to better understand how to debug the output is appreciated!

[1] http://arago-project.org/git/projects/?p=linux-omap3.git;a=commit;h=89ba11fc993b57bfc33d794621788b5158431a7c
[2] http://arago-project.org/git/projects/?p=u-boot-omap3.git;a=commit;h=7683ca6af43c17cf8214e9a241cd63c0001a59b1
[3] http://arago-project.org/git/projects/?p=x-load-omap3.git;a=commit;h=1d3578a5c6cd5967e067bac63670e88d11b6fe4d

Peter Barada
[email protected]

Hi Peter,

Peter Barada <[email protected]> writes:

[...]

I'm afraid somone who supports that older TI kernel will have to help you out.

If you can reproduce on a current kernel, I'd be glad to help but I'm currently not able (well, not willing is more accurate) to try and figure out what's going on based on an older kernel with who knows how many out-of-tree patches/hacks piled on.

What I can say based on the register dump you shared is that there is no obvious driver issue going on where a clock was left on by a driver.

More than likely what is going on is that the booloader is using a device (e.g. USB, MMC) but is leaving it in a state such that that IP block cannot idle, so the CORE powerdomain then does not fully idle. In older kernels like this one, the linux drivers did not fully reset the hardware so bootloaders could cause problems like this (the u-boot on beagle has had several problems like this.)

As a first whack at things, I would focus on USB OTG and MMC, as I've seen problem with both on other platforms, like Beagle. You need to ensure that both the these modules are fully reset either by the bootloader when it's done using them, or by the kernel in the early boot process. Current kernels now do the latter.

Sorry I can't be of more help,

Kevin

[Hiremath, Vaibhav] Peter,

I have validated the release kernel (along with x-loader/uboot) on OMAP3EVM, and it does work without any issues.

I have personally validated this with latest Arago repos, probably you may want to share the changes you have made in x-loader/uboot/kernel to port PSP2.6.32 to LogicPD hardware.

Thanks,
Vaibhav

[Barada, Peter] Viabhav, I've also validated that the x-loader/u-boot/kernel built from the OMAPPSP_03.00.01.06 tags suspends on the DM3730EVM hardware. I'llp ut together a set of patches to those and send you a pointer where to find them. What I'm trying now is to cut board-omap3evm.c down to just the serial/mmc to see if the DM3730EVM shows the same effect; it could be that u-boot has put some of the hardware into a state that the kernel handles in the suspend path but my minimal kernel doesn't. At least that would tell me I'm on the right path.

Peter Barada
[email protected]

I've tried with a newer kernel and see different results:
http://dchs.spinics.net/lists/linux-omap/msg49235.html

How can I determine if an IP block is not idled? Any suggestion where to add code into the suspend patch to do such a check?

Hmm, where in the current kernel is this done, device driver probe functions or common platform init code?

Peter Barada
[email protected]

Peter Barada <[email protected]> writes:

[...]

Unfortunatly, there is no easy way for OMAP3-based platforms. There are unfortunately several things that can be (mis)configured such that an IP
block will not properly idle. This is one of the reasons that
omap_hwmod was introduced. It gives a uniform way for IP blocks to be enabled, idled and shutdown so they are in an a known state.

As part of the initializion of omap_hwmod for a given IP block, the module is reset.

Kevin

[Hiremath, Vaibhav] Does this mean, the issue is only seen on your custom board and not on DM3730EVM?

Thanks,
Vaibhav