[U-Boot] [PATCH v3] nios2: convert nios2 cpu to driver model

[Thomas Chou]

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 <thomas at wytron.com.tw>
---
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(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index 207c778..9be1538 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -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"
diff --git a/arch/nios2/cpu/cpu.c b/arch/nios2/cpu/cpu.c
index 39ae972..9e98742 100644
--- a/arch/nios2/cpu/cpu.c
+++ b/arch/nios2/cpu/cpu.c
@@ -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 +53,77 @@ 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);
+	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);
+	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);
+	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,
+};
diff --git a/arch/nios2/dts/3c120_devboard.dts b/arch/nios2/dts/3c120_devboard.dts
index 781a652..2e2956f 100644
--- a/arch/nios2/dts/3c120_devboard.dts
+++ b/arch/nios2/dts/3c120_devboard.dts
@@ -41,6 +41,7 @@
 			altr,exception-addr = <0xd0000020>;
 			altr,has-initda = <1>;
 			altr,has-mmu = <1>;
+			u-boot,dm-pre-reloc;
 		};
 	};
 
diff --git a/arch/nios2/include/asm/global_data.h b/arch/nios2/include/asm/global_data.h
index 580b019..ee5180b 100644
--- a/arch/nios2/include/asm/global_data.h
+++ b/arch/nios2/include/asm/global_data.h
@@ -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>
diff --git a/configs/nios2-generic_defconfig b/configs/nios2-generic_defconfig
index ad72272..707ee33 100644
--- a/configs/nios2-generic_defconfig
+++ b/configs/nios2-generic_defconfig
@@ -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