alistair23-linux/arch/arm/mach-tegra/fuse.c
Prashant Gaikwad c7736edf1b ARM: tegra: add function to read chipid
Add function to read chip id from APB MISC registers. This function
will also get called from clock driver to flush write operations on
apb bus.

Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-01-28 11:19:06 -07:00

164 lines
4 KiB
C

/*
* arch/arm/mach-tegra/fuse.c
*
* Copyright (C) 2010 Google, Inc.
*
* Author:
* Colin Cross <ccross@android.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/export.h>
#include <linux/tegra-soc.h>
#include "fuse.h"
#include "iomap.h"
#include "apbio.h"
#define FUSE_UID_LOW 0x108
#define FUSE_UID_HIGH 0x10c
#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 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.
*/
int tegra_bct_strapping;
#define STRAP_OPT 0x008
#define GMI_AD0 (1 << 4)
#define GMI_AD1 (1 << 5)
#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",
};
u32 tegra_fuse_readl(unsigned long offset)
{
return tegra_apb_readl(TEGRA_FUSE_BASE + offset);
}
bool tegra_spare_fuse(int bit)
{
return tegra_fuse_readl(tegra_fuse_spare_bit + bit * 4);
}
static enum tegra_revision tegra_get_revision(u32 id)
{
u32 minor_rev = (id >> 16) & 0xf;
switch (minor_rev) {
case 1:
return TEGRA_REVISION_A01;
case 2:
return TEGRA_REVISION_A02;
case 3:
if (tegra_chip_id == TEGRA20 &&
(tegra_spare_fuse(18) || tegra_spare_fuse(19)))
return TEGRA_REVISION_A03p;
else
return TEGRA_REVISION_A03;
case 4:
return TEGRA_REVISION_A04;
default:
return TEGRA_REVISION_UNKNOWN;
}
}
static void tegra_get_process_id(void)
{
u32 reg;
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;
}
u32 tegra_read_chipid(void)
{
return readl_relaxed(IO_ADDRESS(TEGRA_APB_MISC_BASE) + 0x804);
}
void tegra_init_fuse(void)
{
u32 id;
u32 reg = readl(IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));
reg |= 1 << 28;
writel(reg, IO_ADDRESS(TEGRA_CLK_RESET_BASE + 0x48));
reg = tegra_fuse_readl(FUSE_SKU_INFO);
tegra_sku_id = reg & 0xFF;
reg = tegra_apb_readl(TEGRA_APB_MISC_BASE + STRAP_OPT);
tegra_bct_strapping = (reg & RAM_ID_MASK) >> RAM_CODE_SHIFT;
id = tegra_read_chipid();
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;
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();
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);
}
unsigned long long tegra_chip_uid(void)
{
unsigned long long lo, hi;
lo = tegra_fuse_readl(FUSE_UID_LOW);
hi = tegra_fuse_readl(FUSE_UID_HIGH);
return (hi << 32ull) | lo;
}
EXPORT_SYMBOL(tegra_chip_uid);