[PATCH v2 4/6] ARM: tegra: rework fuse.c

From: Peter De Schrijver
Date: Tue Dec 24 2013 - 08:34:43 EST


Reduce fuse.c to the minimum functionality required for the early bootstages.
Also export tegra_read_straps() for use by the fuse driver.

Signed-off-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
---
arch/arm/mach-tegra/fuse.c | 147 ++------------------------------------------
include/linux/tegra-soc.h | 1 +
2 files changed, 7 insertions(+), 141 deletions(-)

diff --git a/arch/arm/mach-tegra/fuse.c b/arch/arm/mach-tegra/fuse.c
index c9ac23b..bad46e5 100644
--- a/arch/arm/mach-tegra/fuse.c
+++ b/arch/arm/mach-tegra/fuse.c
@@ -29,36 +29,14 @@
#include "iomap.h"
#include "apbio.h"

-/* Tegra20 only */
#define FUSE_UID_LOW 0x108
#define FUSE_UID_HIGH 0x10c

-/* Tegra30 and later */
-#define FUSE_VENDOR_CODE 0x200
-#define FUSE_FAB_CODE 0x204
-#define FUSE_LOT_CODE_0 0x208
-#define FUSE_LOT_CODE_1 0x20c
-#define FUSE_WAFER_ID 0x210
-#define FUSE_X_COORDINATE 0x214
-#define FUSE_Y_COORDINATE 0x218
-
-#define FUSE_SKU_INFO 0x110
-
#define TEGRA20_FUSE_SPARE_BIT 0x200
-#define TEGRA30_FUSE_SPARE_BIT 0x244

-int tegra_sku_id;
-int tegra_cpu_process_id;
-int tegra_core_process_id;
int tegra_chip_id;
-int tegra_cpu_speedo_id; /* only exist in Tegra30 and later */
-int tegra_soc_speedo_id;
enum tegra_revision tegra_revision;

-static struct clk *fuse_clk;
-static int tegra_fuse_spare_bit;
-static void (*tegra_init_speedo_data)(void);
-
/* The BCT to use at boot is specified by board straps that can be read
* through a APB misc register and decoded. 2 bits, i.e. 4 possible BCTs.
*/
@@ -70,31 +48,6 @@ int tegra_bct_strapping;
#define RAM_ID_MASK (GMI_AD0 | GMI_AD1)
#define RAM_CODE_SHIFT 4

-static const char *tegra_revision_name[TEGRA_REVISION_MAX] = {
- [TEGRA_REVISION_UNKNOWN] = "unknown",
- [TEGRA_REVISION_A01] = "A01",
- [TEGRA_REVISION_A02] = "A02",
- [TEGRA_REVISION_A03] = "A03",
- [TEGRA_REVISION_A03p] = "A03 prime",
- [TEGRA_REVISION_A04] = "A04",
-};
-
-static void tegra_fuse_enable_clk(void)
-{
- if (IS_ERR(fuse_clk))
- fuse_clk = clk_get_sys(NULL, "fuse");
- if (IS_ERR(fuse_clk))
- return;
- clk_prepare_enable(fuse_clk);
-}
-
-static void tegra_fuse_disable_clk(void)
-{
- if (IS_ERR(fuse_clk))
- return;
- clk_disable_unprepare(fuse_clk);
-}
-
u32 tegra_fuse_readl(unsigned long offset)
{
return tegra_apb_readl(TEGRA_FUSE_BASE + offset);
@@ -102,15 +55,7 @@ u32 tegra_fuse_readl(unsigned long offset)

bool tegra_spare_fuse(int bit)
{
- bool ret;
-
- tegra_fuse_enable_clk();
-
- ret = tegra_fuse_readl(tegra_fuse_spare_bit + bit * 4);
-
- tegra_fuse_disable_clk();
-
- return ret;
+ return tegra_fuse_readl(TEGRA20_FUSE_SPARE_BIT + bit * 4);
}

static enum tegra_revision tegra_get_revision(u32 id)
@@ -135,18 +80,9 @@ static enum tegra_revision tegra_get_revision(u32 id)
}
}

-static void tegra_get_process_id(void)
+u32 tegra_read_straps(void)
{
- u32 reg;
-
- tegra_fuse_enable_clk();
-
- reg = tegra_fuse_readl(tegra_fuse_spare_bit);
- tegra_cpu_process_id = (reg >> 6) & 3;
- reg = tegra_fuse_readl(tegra_fuse_spare_bit);
- tegra_core_process_id = (reg >> 12) & 3;
-
- tegra_fuse_disable_clk();
+ return tegra_apb_readl(TEGRA_APB_MISC_BASE + STRAP_OPT);
}

u32 tegra_read_chipid(void)
@@ -154,38 +90,12 @@ u32 tegra_read_chipid(void)
return readl_relaxed(IO_ADDRESS(TEGRA_APB_MISC_BASE) + 0x804);
}

-static void __init tegra20_fuse_init_randomness(void)
-{
- u32 randomness[2];
-
- randomness[0] = tegra_fuse_readl(FUSE_UID_LOW);
- randomness[1] = tegra_fuse_readl(FUSE_UID_HIGH);
-
- add_device_randomness(randomness, sizeof(randomness));
-}
-
-/* Applies to Tegra30 or later */
-static void __init tegra30_fuse_init_randomness(void)
-{
- u32 randomness[7];
-
- randomness[0] = tegra_fuse_readl(FUSE_VENDOR_CODE);
- randomness[1] = tegra_fuse_readl(FUSE_FAB_CODE);
- randomness[2] = tegra_fuse_readl(FUSE_LOT_CODE_0);
- randomness[3] = tegra_fuse_readl(FUSE_LOT_CODE_1);
- randomness[4] = tegra_fuse_readl(FUSE_WAFER_ID);
- randomness[5] = tegra_fuse_readl(FUSE_X_COORDINATE);
- randomness[6] = tegra_fuse_readl(FUSE_Y_COORDINATE);
-
- add_device_randomness(randomness, sizeof(randomness));
-}
-
void __init tegra_init_fuse(void)
{
u32 id;
- u32 randomness[5];
+ u32 reg;

- u32 reg = readl(IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));
+ reg = readl(IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));
reg |= 1 << 28;
writel(reg, IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));

@@ -196,57 +106,12 @@ void __init tegra_init_fuse(void)
reg = readl(IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x14));
reg |= 1 << 7;
writel(reg, IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x14));
- fuse_clk = ERR_PTR(-EINVAL);
-
- reg = tegra_fuse_readl(FUSE_SKU_INFO);
- randomness[0] = reg;
- tegra_sku_id = reg & 0xFF;

- reg = tegra_apb_readl(TEGRA_APB_MISC_BASE + STRAP_OPT);
- randomness[1] = reg;
+ reg = tegra_read_straps();
tegra_bct_strapping = (reg & RAM_ID_MASK) >> RAM_CODE_SHIFT;

id = tegra_read_chipid();
- randomness[2] = id;
tegra_chip_id = (id >> 8) & 0xff;

- switch (tegra_chip_id) {
- case TEGRA20:
- tegra_fuse_spare_bit = TEGRA20_FUSE_SPARE_BIT;
- tegra_init_speedo_data = &tegra20_init_speedo_data;
- break;
- case TEGRA30:
- tegra_fuse_spare_bit = TEGRA30_FUSE_SPARE_BIT;
- tegra_init_speedo_data = &tegra30_init_speedo_data;
- break;
- case TEGRA114:
- tegra_init_speedo_data = &tegra114_init_speedo_data;
- break;
- default:
- pr_warn("Tegra: unknown chip id %d\n", tegra_chip_id);
- tegra_fuse_spare_bit = TEGRA20_FUSE_SPARE_BIT;
- tegra_init_speedo_data = &tegra_get_process_id;
- }
-
tegra_revision = tegra_get_revision(id);
- tegra_init_speedo_data();
- randomness[3] = (tegra_cpu_process_id << 16) | tegra_core_process_id;
- randomness[4] = (tegra_cpu_speedo_id << 16) | tegra_soc_speedo_id;
-
- add_device_randomness(randomness, sizeof(randomness));
- switch (tegra_chip_id) {
- case TEGRA20:
- tegra20_fuse_init_randomness();
- break;
- case TEGRA30:
- case TEGRA114:
- default:
- tegra30_fuse_init_randomness();
- break;
- }
-
- pr_info("Tegra Revision: %s SKU: %d CPU Process: %d Core Process: %d\n",
- tegra_revision_name[tegra_revision],
- tegra_sku_id, tegra_cpu_process_id,
- tegra_core_process_id);
}
diff --git a/include/linux/tegra-soc.h b/include/linux/tegra-soc.h
index f53fe9c..8805f3f 100644
--- a/include/linux/tegra-soc.h
+++ b/include/linux/tegra-soc.h
@@ -17,6 +17,7 @@
#ifndef __LINUX_TEGRA_SOC_H_
#define __LINUX_TEGRA_SOC_H_

+u32 tegra_read_straps(void);
u32 tegra_read_chipid(void);


--
1.7.7.rc0.72.g4b5ea.dirty

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/