nios2: convert nios2 cpu to driver model

Convert nios2 cpu to driver model. The cpu parameters are extracted from device tree and saved to global data structure. We will use them to replace the custom_fpga.h .

Signed-off-by Thomas Chou <[email protected]>

---
v2
move cpu param setup to arch_cpu_init_dm, remove probe.

 arch/Kconfig                         |  3 ++
 arch/nios2/cpu/cpu.c                 | 76
++++++++++++++++++++++++++++++++++-- arch/nios2/dts/3c120_devboard.dts   
|  1 +
 arch/nios2/include/asm/global_data.h |  8 ++++
 configs/nios2-generic_defconfig      |  2 -
 5 files changed, 85 insertions(+), 5 deletions(-)

arch/Kconfig +0 -0

index 207c778..9be1538 100644

arch/Kconfig +0 -0

 config OPENRISC
 	bool "OpenRISC architecture"

arch/nios2/cpu/cpu.c +16 -3

index 39ae972..88984e2 100644
@@ -6,7 +6,9 @@
  */
 
 #include <common.h>
-#include <asm/nios2.h>
+#include <cpu.h>
+#include <dm.h>
+#include <errno.h>
 #include <asm/cache.h>
 
 DECLARE_GLOBAL_DATA_PTR;

@@ -51,10 +53,78 @@ void dcache_disable(void)
 	flush_dcache(CONFIG_SYS_DCACHE_SIZE, CONFIG_SYS_DCACHELINE_SIZE);
 }
 
-int arch_cpu_init(void)
+int arch_cpu_init_dm(void)
 {
-	gd->cpu_clk = CONFIG_SYS_CLK_FREQ;
+	struct udevice *dev;
+
+	uclass_first_device(UCLASS_CPU, &dev);
+	if (!dev)
+		return -ENODEV;
+
+	gd->cpu_clk = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"clock-frequency", 0);
+	gd->arch.dcache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"dcache-line-size", 0);
+	gd->arch.icache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"icache-line-size", 0);

arch/nios2/cpu/cpu.c +14 -0

+	gd->arch.io_region_base = gd->arch.has_mmu ? 0xe0000000 : 0x8000000;
 	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
 
 	return 0;
 }
+
+static int altera_nios2_get_desc(struct udevice *dev, char *buf, int size)
+{
+	const char *cpu_name = "Nios-II";
+
+	if (size < strlen(cpu_name))
+		return -ENOSPC;
+	strcpy(buf, cpu_name);
+
+	return 0;
+}
+
+static int altera_nios2_get_info(struct udevice *dev, struct cpu_info

*info) +{

arch/Kconfig config NIOS2 · line 69

Quoted 9 lines

arch/Kconfig +3 -0

@@ -64,6 +64,9 @@ config NIOS2
  	select HAVE_GENERIC_BOARD
  	select SYS_GENERIC_BOARD
  	select SUPPORT_OF_CONTROL
+	select OF_CONTROL
+	select DM
+	select CPU

What's this CONFIG_CPU for please ?

Quoted 20 lines

arch/Kconfig +17 -2

-int arch_cpu_init(void)
+int arch_cpu_init_dm(void)
  {
-	gd->cpu_clk = CONFIG_SYS_CLK_FREQ;
+	struct udevice *dev;
+
+	uclass_first_device(UCLASS_CPU, &dev);
+	if (!dev)
+		return -ENODEV;
+
+	gd->cpu_clk = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"clock-frequency", 0);
+	gd->arch.dcache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"dcache-line-size", 0);
+	gd->arch.icache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"icache-line-size", 0);
+	gd->arch.dcache_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"dcache-size", 0);
+	gd->arch.icache_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"icache-size", 0);

arch/Kconfig

Quoted 6 lines

arch/Kconfig +6 -0

+	gd->arch.reset_addr = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"altr,reset-addr", 0);
+	gd->arch.exception_addr = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"altr,exception-addr", 0);
+	gd->arch.has_mmu = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"altr,has-mmu", 0);

Shouldn't there be some sort of return value checking here ?

arch/Kconfig

Quoted 3 lines

arch/Kconfig +2 -0

+	info->features = 1 << CPU_FEAT_L1_CACHE
+		| (gd->arch.has_mmu ? 1 << CPU_FEAT_MMU : 0);

I'd add parenthesis around the bitshifts, for the sake of clarity. Also, please put the ORR operator at the end of the line.

Hi Marek,

Quoted 13 lines · Marek Vasut

arch/Kconfig config NIOS2 · line 69

Quoted 10 lines

arch/Kconfig +3 -0

@@ -64,6 +64,9 @@ config NIOS2
        select HAVE_GENERIC_BOARD
        select SYS_GENERIC_BOARD
        select SUPPORT_OF_CONTROL
+       select OF_CONTROL
+       select DM
+       select CPU

What's this CONFIG_CPU for please ?

drivers/cpu/Kconfig

It is "Enable CPU drivers using Driver Model". I think it should have been named as CONFIG_DM_CPU to avoid confusion.

+Simon

Quoted 18 lines · Thomas Chou

Hi Marek,

Quoted 13 lines · Marek Vasut

arch/Kconfig config NIOS2 · line 69

Quoted 10 lines

arch/Kconfig +3 -0

@@ -64,6 +64,9 @@ config NIOS2
        select HAVE_GENERIC_BOARD
        select SYS_GENERIC_BOARD
        select SUPPORT_OF_CONTROL
+       select OF_CONTROL
+       select DM
+       select CPU

What's this CONFIG_CPU for please ?

Quoted 4 lines

drivers/cpu/Kconfig

It is "Enable CPU drivers using Driver Model". I think it should have been named as CONFIG_DM_CPU to avoid confusion.

I remember Simon intended to name it as CONFIG_DM_CPU as I raised similar comments before.

[snip]

Regards,
Bin

Quoted 23 lines · Bin Meng

+Simon

Quoted 20 lines · Thomas Chou

Hi Marek,

Quoted 13 lines · Marek Vasut

arch/Kconfig config NIOS2 · line 69

Quoted 10 lines

arch/Kconfig +3 -0

@@ -64,6 +64,9 @@ config NIOS2
        select HAVE_GENERIC_BOARD
        select SYS_GENERIC_BOARD
        select SUPPORT_OF_CONTROL
+       select OF_CONTROL
+       select DM
+       select CPU

What's this CONFIG_CPU for please ?

drivers/cpu/Kconfig

Quoted 5 lines

Quoted 2 lines

It is "Enable CPU drivers using Driver Model". I think it should have been named as CONFIG_DM_CPU to avoid confusion.

I remember Simon intended to name it as CONFIG_DM_CPU as I raised similar comments before.

Oops, I must be drunk! I mean CONFIG_CPU ...

Convert nios2 cpu to driver model. The cpu parameters are extracted from device tree and saved to global data structure. We will use them to replace the custom_fpga.h .

Signed-off-by Thomas Chou <[email protected]>

---
v2
move cpu param setup to arch_cpu_init_dm, remove probe.
v3
fix coding style as Marek suggested.
select CMD_CPU.

 arch/Kconfig                         |  3 ++
 arch/nios2/cpu/cpu.c                 | 75 ++++++++++++++++++++++++++++++++++--
 arch/nios2/dts/3c120_devboard.dts    |  1 +
 arch/nios2/include/asm/global_data.h |  8 ++++
 configs/nios2-generic_defconfig      |  3 +-
 5 files changed, 85 insertions(+), 5 deletions(-)

arch/Kconfig +3 -0

index 207c778..9be1538 100644
@@ -64,6 +64,9 @@ config NIOS2
        select HAVE_GENERIC_BOARD
        select SYS_GENERIC_BOARD
        select SUPPORT_OF_CONTROL
+       select OF_CONTROL
+       select DM
+       select CPU
 
 config OPENRISC
        bool "OpenRISC architecture"

arch/nios2/cpu/cpu.c +3 -1

index 39ae972..9e98742 100644
@@ -6,7 +6,9 @@
  */
 
 #include <common.h>
-#include <asm/nios2.h>
+#include <cpu.h>
+#include <dm.h>
+#include <errno.h>
 #include <asm/cache.h>
 
 DECLARE_GLOBAL_DATA_PTR;

arch/nios2/cpu/cpu.c +5 -0

+               "clock-frequency", 0);
+       gd->arch.dcache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+               "dcache-line-size", 0);
+       gd->arch.icache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+               "icache-line-size", 0);

arch/nios2/cpu/cpu.c +46 -0

+       gd->arch.io_region_base = gd->arch.has_mmu ? 0xe0000000 : 0x8000000;
        gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
 
        return 0;
 }
+
+static int altera_nios2_get_desc(struct udevice *dev, char *buf, int size)
+{
+       const char *cpu_name = "Nios-II";
+
+       if (size < strlen(cpu_name))
+               return -ENOSPC;
+       strcpy(buf, cpu_name);
+
+       return 0;
+}
+
+static int altera_nios2_get_info(struct udevice *dev, struct cpu_info *info)
+{
+       info->cpu_freq = gd->cpu_clk;
+       info->features = (1 << CPU_FEAT_L1_CACHE) |
+               (gd->arch.has_mmu ? (1 << CPU_FEAT_MMU) : 0);
+
+       return 0;
+}
+
+static int altera_nios2_get_count(struct udevice *dev)
+{
+       return 1;
+}
+
+static const struct cpu_ops altera_nios2_ops = {
+       .get_desc       = altera_nios2_get_desc,
+       .get_info       = altera_nios2_get_info,
+       .get_count      = altera_nios2_get_count,
+};
+
+static const struct udevice_id altera_nios2_ids[] = {
+       { .compatible = "altr,nios2-1.0" },
+       { .compatible = "altr,nios2-1.1" },
+       { }
+};
+
+U_BOOT_DRIVER(altera_nios2) = {
+       .name           = "altera_nios2",
+       .id             = UCLASS_CPU,
+       .of_match       = altera_nios2_ids,
+       .ops            = &altera_nios2_ops,
+       .flags          = DM_FLAG_PRE_RELOC,
+};

arch/nios2/dts/3c120_devboard.dts +1 -0

index 781a652..2e2956f 100644
@@ -41,6 +41,7 @@
                        altr,exception-addr = <0xd0000020>;
                        altr,has-initda = <1>;
                        altr,has-mmu = <1>;
+                       u-boot,dm-pre-reloc;
                };
        };
 

arch/nios2/include/asm/global_data.h +8 -0

index 580b019..ee5180b 100644
@@ -9,6 +9,14 @@
 
 /* Architecture-specific global data */
 struct arch_global_data {
+       u32 dcache_line_size;
+       u32 icache_line_size;
+       u32 dcache_size;
+       u32 icache_size;
+       u32 reset_addr;
+       u32 exception_addr;
+       int has_mmu;
+       u32 io_region_base;
 };
 
 #include <asm-generic/global_data.h>

configs/nios2-generic_defconfig +1 -3

index ad72272..707ee33 100644
@@ -4,6 +4,7 @@ CONFIG_DM_GPIO=y
 CONFIG_TARGET_NIOS2_GENERIC=y
 CONFIG_DEFAULT_DEVICE_TREE="3c120_devboard"
 CONFIG_HUSH_PARSER=y
+CONFIG_CMD_CPU=y
 # CONFIG_CMD_BOOTD is not set
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_XIMG is not set

@@ -13,9 +14,7 @@ CONFIG_HUSH_PARSER=y
 CONFIG_CMD_DHCP=y
 # CONFIG_CMD_NFS is not set
 CONFIG_CMD_PING=y
-CONFIG_OF_CONTROL=y
 CONFIG_NET_RANDOM_ETHADDR=y
-CONFIG_DM=y
 CONFIG_ALTERA_PIO=y
 CONFIG_ALTERA_JTAG_UART=y
 CONFIG_ALTERA_JTAG_UART_BYPASS=y
--

2.1.4

arch/nios2/cpu/cpu.c void dcache_disable(void) · line 79

Quoted 2 lines

arch/nios2/cpu/cpu.c +2 -0

+       gd->arch.has_mmu = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+               "altr,has-mmu", 0);

Should that be fdtdec_get_bool()? Also is there a device tree binding file for these settings?

Convert nios2 cpu to driver model. The cpu parameters are extracted from device tree and saved to global data structure. We will use them to replace the custom_fpga.h .

Signed-off-by Thomas Chou <[email protected]>

---
v2
move cpu param setup to arch_cpu_init_dm, remove probe.
v3
fix coding style as Marek suggested.
select CMD_CPU.
v4
revert to v1 probe method.
doc dts binding.
check uclass_first_device() return.
clean up as Simon suggested.

 arch/Kconfig                           |  3 ++
 arch/nios2/cpu/cpu.c                   | 88 ++++++++++++++++++++++++++++++++--
 arch/nios2/dts/3c120_devboard.dts      |  1 +
 arch/nios2/include/asm/global_data.h   |  8 ++++
 configs/nios2-generic_defconfig        |  3 +-
 doc/device-tree-bindings/cpu/nios2.txt | 54 +++++++++++++++++++++
 6 files changed, 152 insertions(+), 5 deletions(-)
 create mode 100644 doc/device-tree-bindings/cpu/nios2.txt

Convert nios2 cpu to driver model. The cpu parameters are extracted from device tree and saved to global data structure. We will use them to replace the custom_fpga.h .

Signed-off-by Thomas Chou <[email protected]>

---
v2
move cpu param setup to arch_cpu_init_dm, remove probe.
v3
fix coding style as Marek suggested.
select CMD_CPU.
v4
revert to v1 probe method.
doc dts binding.
check uclass_first_device() return.
clean up as Simon suggested.

  arch/Kconfig                           |  3 ++
  arch/nios2/cpu/cpu.c                   | 88 ++++++++++++++++++++++++++++++++--
  arch/nios2/dts/3c120_devboard.dts      |  1 +
  arch/nios2/include/asm/global_data.h   |  8 ++++
  configs/nios2-generic_defconfig        |  3 +-
  doc/device-tree-bindings/cpu/nios2.txt | 54 +++++++++++++++++++++
  6 files changed, 152 insertions(+), 5 deletions(-)

create mode 100644 doc/device-tree-bindings/cpu/nios2.txt