u-boot/arch/arm/mach-imx/imx9/soc.c
Peng Fan 58da865e27 imx9: add i.MX93 variants support
According to datasheet, iMX93 has fused parts with CORE1 or NPU or
both disabled. So update code to support it, the kernel device tree
runtime update will be added in future patches.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
2023-05-21 16:54:41 +02:00

813 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2022 NXP
*
* Peng Fan <peng.fan@nxp.com>
*/
#include <common.h>
#include <cpu_func.h>
#include <init.h>
#include <log.h>
#include <asm/arch/imx-regs.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/ccm_regs.h>
#include <asm/arch/sys_proto.h>
#include <asm/arch/trdc.h>
#include <asm/mach-imx/boot_mode.h>
#include <asm/mach-imx/syscounter.h>
#include <asm/armv8/mmu.h>
#include <dm/device.h>
#include <dm/device_compat.h>
#include <dm/uclass.h>
#include <env.h>
#include <env_internal.h>
#include <errno.h>
#include <fdt_support.h>
#include <imx_thermal.h>
#include <linux/bitops.h>
#include <linux/bitfield.h>
#include <linux/delay.h>
#include <thermal.h>
#include <asm/setup.h>
#include <asm/bootm.h>
#include <asm/arch-imx/cpu.h>
#include <asm/mach-imx/s400_api.h>
#include <fuse.h>
DECLARE_GLOBAL_DATA_PTR;
struct rom_api *g_rom_api = (struct rom_api *)0x1980;
#ifdef CONFIG_ENV_IS_IN_MMC
__weak int board_mmc_get_env_dev(int devno)
{
return devno; }
int mmc_get_env_dev(void)
{
volatile gd_t *pgd = gd;
int ret;
u32 boot;
u16 boot_type;
u8 boot_instance;
ret = g_rom_api->query_boot_infor(QUERY_BT_DEV, &boot,
((uintptr_t)&boot) ^ QUERY_BT_DEV);
set_gd(pgd);
if (ret != ROM_API_OKAY) {
puts("ROMAPI: failure at query_boot_info\n");
return CONFIG_SYS_MMC_ENV_DEV;
}
boot_type = boot >> 16;
boot_instance = (boot >> 8) & 0xff;
debug("boot_type %d, instance %d\n", boot_type, boot_instance);
/* If not boot from sd/mmc, use default value */
if (boot_type != BOOT_TYPE_SD && boot_type != BOOT_TYPE_MMC)
return env_get_ulong("mmcdev", 10, CONFIG_SYS_MMC_ENV_DEV);
return board_mmc_get_env_dev(boot_instance);
}
#endif
/*
* SPEED_GRADE[5:4] SPEED_GRADE[3:0] MHz
* xx 0000 2300
* xx 0001 2200
* xx 0010 2100
* xx 0011 2000
* xx 0100 1900
* xx 0101 1800
* xx 0110 1700
* xx 0111 1600
* xx 1000 1500
* xx 1001 1400
* xx 1010 1300
* xx 1011 1200
* xx 1100 1100
* xx 1101 1000
* xx 1110 900
* xx 1111 800
*/
u32 get_cpu_speed_grade_hz(void)
{
u32 speed, max_speed;
u32 val;
fuse_read(2, 3, &val);
val = FIELD_GET(SPEED_GRADING_MASK, val) & 0xF;
speed = MHZ(2300) - val * MHZ(100);
if (is_imx93())
max_speed = MHZ(1700);
/* In case the fuse of speed grade not programmed */
if (speed > max_speed)
speed = max_speed;
return speed;
}
/*
* `00` - Consumer 0C to 95C
* `01` - Ext. Consumer -20C to 105C
* `10` - Industrial -40C to 105C
* `11` - Automotive -40C to 125C
*/
u32 get_cpu_temp_grade(int *minc, int *maxc)
{
u32 val;
fuse_read(2, 3, &val);
val = FIELD_GET(MARKETING_GRADING_MASK, val);
if (minc && maxc) {
if (val == TEMP_AUTOMOTIVE) {
*minc = -40;
*maxc = 125;
} else if (val == TEMP_INDUSTRIAL) {
*minc = -40;
*maxc = 105;
} else if (val == TEMP_EXTCOMMERCIAL) {
if (is_imx93()) {
/* imx93 only has extended industrial*/
*minc = -40;
*maxc = 125;
} else {
*minc = -20;
*maxc = 105;
}
} else {
*minc = 0;
*maxc = 95;
}
}
return val;
}
static void set_cpu_info(struct sentinel_get_info_data *info)
{
gd->arch.soc_rev = info->soc;
gd->arch.lifecycle = info->lc;
memcpy((void *)&gd->arch.uid, &info->uid, 4 * sizeof(u32));
}
static u32 get_cpu_variant_type(u32 type)
{
/* word 19 */
u32 val = readl((ulong)FSB_BASE_ADDR + 0x8000 + (19 << 2));
u32 val2 = readl((ulong)FSB_BASE_ADDR + 0x8000 + (20 << 2));
bool npu_disable = !!(val & BIT(13));
bool core1_disable = !!(val & BIT(15));
u32 pack_9x9_fused = BIT(4) | BIT(17) | BIT(19) | BIT(24);
if ((val2 & pack_9x9_fused) == pack_9x9_fused)
type = MXC_CPU_IMX9322;
if (npu_disable && core1_disable)
return type + 3;
else if (npu_disable)
return type + 2;
else if (core1_disable)
return type + 1;
return type;
}
u32 get_cpu_rev(void)
{
u32 rev = (gd->arch.soc_rev >> 24) - 0xa0;
return (get_cpu_variant_type(MXC_CPU_IMX93) << 12) |
(CHIP_REV_1_0 + rev);
}
#define UNLOCK_WORD 0xD928C520 /* unlock word */
#define REFRESH_WORD 0xB480A602 /* refresh word */
static void disable_wdog(void __iomem *wdog_base)
{
u32 val_cs = readl(wdog_base + 0x00);
if (!(val_cs & 0x80))
return;
/* default is 32bits cmd */
writel(REFRESH_WORD, (wdog_base + 0x04)); /* Refresh the CNT */
if (!(val_cs & 0x800)) {
writel(UNLOCK_WORD, (wdog_base + 0x04));
while (!(readl(wdog_base + 0x00) & 0x800))
;
}
writel(0x0, (wdog_base + 0x0C)); /* Set WIN to 0 */
writel(0x400, (wdog_base + 0x08)); /* Set timeout to default 0x400 */
writel(0x2120, (wdog_base + 0x00)); /* Disable it and set update */
while (!(readl(wdog_base + 0x00) & 0x400))
;
}
void init_wdog(void)
{
u32 src_val;
disable_wdog((void __iomem *)WDG3_BASE_ADDR);
disable_wdog((void __iomem *)WDG4_BASE_ADDR);
disable_wdog((void __iomem *)WDG5_BASE_ADDR);
src_val = readl(0x54460018); /* reset mask */
src_val &= ~0x1c;
writel(src_val, 0x54460018);
}
static struct mm_region imx93_mem_map[] = {
{
/* ROM */
.virt = 0x0UL,
.phys = 0x0UL,
.size = 0x100000UL,
.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
PTE_BLOCK_OUTER_SHARE
}, {
/* TCM */
.virt = 0x201c0000UL,
.phys = 0x201c0000UL,
.size = 0x80000UL,
.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
PTE_BLOCK_NON_SHARE |
PTE_BLOCK_PXN | PTE_BLOCK_UXN
}, {
/* OCRAM */
.virt = 0x20480000UL,
.phys = 0x20480000UL,
.size = 0xA0000UL,
.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
PTE_BLOCK_OUTER_SHARE
}, {
/* AIPS */
.virt = 0x40000000UL,
.phys = 0x40000000UL,
.size = 0x40000000UL,
.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
PTE_BLOCK_NON_SHARE |
PTE_BLOCK_PXN | PTE_BLOCK_UXN
}, {
/* Flexible Serial Peripheral Interface */
.virt = 0x28000000UL,
.phys = 0x28000000UL,
.size = 0x30000000UL,
.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
PTE_BLOCK_NON_SHARE |
PTE_BLOCK_PXN | PTE_BLOCK_UXN
}, {
/* DRAM1 */
.virt = 0x80000000UL,
.phys = 0x80000000UL,
.size = PHYS_SDRAM_SIZE,
.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
PTE_BLOCK_OUTER_SHARE
}, {
/* empty entrie to split table entry 5 if needed when TEEs are used */
0,
}, {
/* List terminator */
0,
}
};
struct mm_region *mem_map = imx93_mem_map;
static unsigned int imx9_find_dram_entry_in_mem_map(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(imx93_mem_map); i++)
if (imx93_mem_map[i].phys == CFG_SYS_SDRAM_BASE)
return i;
hang(); /* Entry not found, this must never happen. */
}
void enable_caches(void)
{
/* If OPTEE runs, remove OPTEE memory from MMU table to avoid speculative prefetch
* If OPTEE does not run, still update the MMU table according to dram banks structure
* to set correct dram size from board_phys_sdram_size
*/
int i = 0;
/*
* please make sure that entry initial value matches
* imx93_mem_map for DRAM1
*/
int entry = imx9_find_dram_entry_in_mem_map();
u64 attrs = imx93_mem_map[entry].attrs;
while (i < CONFIG_NR_DRAM_BANKS &&
entry < ARRAY_SIZE(imx93_mem_map)) {
if (gd->bd->bi_dram[i].start == 0)
break;
imx93_mem_map[entry].phys = gd->bd->bi_dram[i].start;
imx93_mem_map[entry].virt = gd->bd->bi_dram[i].start;
imx93_mem_map[entry].size = gd->bd->bi_dram[i].size;
imx93_mem_map[entry].attrs = attrs;
debug("Added memory mapping (%d): %llx %llx\n", entry,
imx93_mem_map[entry].phys, imx93_mem_map[entry].size);
i++; entry++;
}
icache_enable();
dcache_enable();
}
__weak int board_phys_sdram_size(phys_size_t *size)
{
if (!size)
return -EINVAL;
*size = PHYS_SDRAM_SIZE;
#ifdef PHYS_SDRAM_2_SIZE
*size += PHYS_SDRAM_2_SIZE;
#endif
return 0;
}
int dram_init(void)
{
phys_size_t sdram_size;
int ret;
ret = board_phys_sdram_size(&sdram_size);
if (ret)
return ret;
/* rom_pointer[1] contains the size of TEE occupies */
if (rom_pointer[1])
gd->ram_size = sdram_size - rom_pointer[1];
else
gd->ram_size = sdram_size;
return 0;
}
int dram_init_banksize(void)
{
int bank = 0;
int ret;
phys_size_t sdram_size;
phys_size_t sdram_b1_size, sdram_b2_size;
ret = board_phys_sdram_size(&sdram_size);
if (ret)
return ret;
/* Bank 1 can't cross over 4GB space */
if (sdram_size > 0x80000000) {
sdram_b1_size = 0x80000000;
sdram_b2_size = sdram_size - 0x80000000;
} else {
sdram_b1_size = sdram_size;
sdram_b2_size = 0;
}
gd->bd->bi_dram[bank].start = PHYS_SDRAM;
if (rom_pointer[1]) {
phys_addr_t optee_start = (phys_addr_t)rom_pointer[0];
phys_size_t optee_size = (size_t)rom_pointer[1];
gd->bd->bi_dram[bank].size = optee_start - gd->bd->bi_dram[bank].start;
if ((optee_start + optee_size) < (PHYS_SDRAM + sdram_b1_size)) {
if (++bank >= CONFIG_NR_DRAM_BANKS) {
puts("CONFIG_NR_DRAM_BANKS is not enough\n");
return -1;
}
gd->bd->bi_dram[bank].start = optee_start + optee_size;
gd->bd->bi_dram[bank].size = PHYS_SDRAM +
sdram_b1_size - gd->bd->bi_dram[bank].start;
}
} else {
gd->bd->bi_dram[bank].size = sdram_b1_size;
}
if (sdram_b2_size) {
if (++bank >= CONFIG_NR_DRAM_BANKS) {
puts("CONFIG_NR_DRAM_BANKS is not enough for SDRAM_2\n");
return -1;
}
gd->bd->bi_dram[bank].start = 0x100000000UL;
gd->bd->bi_dram[bank].size = sdram_b2_size;
}
return 0;
}
phys_size_t get_effective_memsize(void)
{
int ret;
phys_size_t sdram_size;
phys_size_t sdram_b1_size;
ret = board_phys_sdram_size(&sdram_size);
if (!ret) {
/* Bank 1 can't cross over 4GB space */
if (sdram_size > 0x80000000)
sdram_b1_size = 0x80000000;
else
sdram_b1_size = sdram_size;
if (rom_pointer[1]) {
/* We will relocate u-boot to top of dram1. TEE position has two cases:
* 1. At the top of dram1, Then return the size removed optee size.
* 2. In the middle of dram1, return the size of dram1.
*/
if ((rom_pointer[0] + rom_pointer[1]) == (PHYS_SDRAM + sdram_b1_size))
return ((phys_addr_t)rom_pointer[0] - PHYS_SDRAM);
}
return sdram_b1_size;
} else {
return PHYS_SDRAM_SIZE;
}
}
void imx_get_mac_from_fuse(int dev_id, unsigned char *mac)
{
u32 val[2] = {};
int ret;
if (dev_id == 0) {
ret = fuse_read(39, 3, &val[0]);
if (ret)
goto err;
ret = fuse_read(39, 4, &val[1]);
if (ret)
goto err;
mac[0] = val[1] >> 8;
mac[1] = val[1];
mac[2] = val[0] >> 24;
mac[3] = val[0] >> 16;
mac[4] = val[0] >> 8;
mac[5] = val[0];
} else {
ret = fuse_read(39, 5, &val[0]);
if (ret)
goto err;
ret = fuse_read(39, 4, &val[1]);
if (ret)
goto err;
mac[0] = val[1] >> 24;
mac[1] = val[1] >> 16;
mac[2] = val[0] >> 24;
mac[3] = val[0] >> 16;
mac[4] = val[0] >> 8;
mac[5] = val[0];
}
debug("%s: MAC%d: %02x.%02x.%02x.%02x.%02x.%02x\n",
__func__, dev_id, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
return;
err:
memset(mac, 0, 6);
printf("%s: fuse read err: %d\n", __func__, ret);
}
int print_cpuinfo(void)
{
u32 cpurev;
cpurev = get_cpu_rev();
printf("CPU: i.MX93 rev%d.%d\n", (cpurev & 0x000F0) >> 4, (cpurev & 0x0000F) >> 0);
return 0;
}
int ft_system_setup(void *blob, struct bd_info *bd)
{
return 0;
}
#if defined(CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG)
void get_board_serial(struct tag_serialnr *serialnr)
{
printf("UID: 0x%x 0x%x 0x%x 0x%x\n",
gd->arch.uid[0], gd->arch.uid[1], gd->arch.uid[2], gd->arch.uid[3]);
serialnr->low = gd->arch.uid[0];
serialnr->high = gd->arch.uid[3];
}
#endif
static void save_reset_cause(void)
{
struct src_general_regs *src = (struct src_general_regs *)SRC_GLOBAL_RBASE;
u32 srsr = readl(&src->srsr);
/* clear srsr in sec mode */
writel(srsr, &src->srsr);
/* Save value to GPR1 to pass to nonsecure */
writel(srsr, &src->gpr[0]);
}
int arch_cpu_init(void)
{
if (IS_ENABLED(CONFIG_SPL_BUILD)) {
/* Disable wdog */
init_wdog();
clock_init();
trdc_early_init();
/* Save SRC SRSR to GPR1 and clear it */
save_reset_cause();
}
return 0;
}
int imx9_probe_mu(void *ctx, struct event *event)
{
struct udevice *devp;
int node, ret;
u32 res;
struct sentinel_get_info_data info;
node = fdt_node_offset_by_compatible(gd->fdt_blob, -1, "fsl,imx93-mu-s4");
ret = uclass_get_device_by_of_offset(UCLASS_MISC, node, &devp);
if (ret)
return ret;
if (gd->flags & GD_FLG_RELOC)
return 0;
ret = ahab_get_info(&info, &res);
if (ret)
return ret;
set_cpu_info(&info);
return 0;
}
EVENT_SPY(EVT_DM_POST_INIT_F, imx9_probe_mu);
int timer_init(void)
{
#ifdef CONFIG_SPL_BUILD
struct sctr_regs *sctr = (struct sctr_regs *)SYSCNT_CTRL_BASE_ADDR;
unsigned long freq = readl(&sctr->cntfid0);
/* Update with accurate clock frequency */
asm volatile("msr cntfrq_el0, %0" : : "r" (freq) : "memory");
clrsetbits_le32(&sctr->cntcr, SC_CNTCR_FREQ0 | SC_CNTCR_FREQ1,
SC_CNTCR_FREQ0 | SC_CNTCR_ENABLE | SC_CNTCR_HDBG);
#endif
gd->arch.tbl = 0;
gd->arch.tbu = 0;
return 0;
}
enum env_location env_get_location(enum env_operation op, int prio)
{
enum boot_device dev = get_boot_device();
enum env_location env_loc = ENVL_UNKNOWN;
if (prio)
return env_loc;
switch (dev) {
#if defined(CONFIG_ENV_IS_IN_SPI_FLASH)
case QSPI_BOOT:
env_loc = ENVL_SPI_FLASH;
break;
#endif
#if defined(CONFIG_ENV_IS_IN_MMC)
case SD1_BOOT:
case SD2_BOOT:
case SD3_BOOT:
case MMC1_BOOT:
case MMC2_BOOT:
case MMC3_BOOT:
env_loc = ENVL_MMC;
break;
#endif
default:
#if defined(CONFIG_ENV_IS_NOWHERE)
env_loc = ENVL_NOWHERE;
#endif
break;
}
return env_loc;
}
static int mix_power_init(enum mix_power_domain pd)
{
enum src_mix_slice_id mix_id;
enum src_mem_slice_id mem_id;
struct src_mix_slice_regs *mix_regs;
struct src_mem_slice_regs *mem_regs;
struct src_general_regs *global_regs;
u32 scr, val;
switch (pd) {
case MIX_PD_MEDIAMIX:
mix_id = SRC_MIX_MEDIA;
mem_id = SRC_MEM_MEDIA;
scr = BIT(5);
/* Enable S400 handshake */
struct blk_ctrl_s_aonmix_regs *s_regs =
(struct blk_ctrl_s_aonmix_regs *)BLK_CTRL_S_ANOMIX_BASE_ADDR;
setbits_le32(&s_regs->lp_handshake[0], BIT(13));
break;
case MIX_PD_MLMIX:
mix_id = SRC_MIX_ML;
mem_id = SRC_MEM_ML;
scr = BIT(4);
break;
case MIX_PD_DDRMIX:
mix_id = SRC_MIX_DDRMIX;
mem_id = SRC_MEM_DDRMIX;
scr = BIT(6);
break;
default:
return -EINVAL;
}
mix_regs = (struct src_mix_slice_regs *)(ulong)(SRC_IPS_BASE_ADDR + 0x400 * (mix_id + 1));
mem_regs =
(struct src_mem_slice_regs *)(ulong)(SRC_IPS_BASE_ADDR + 0x3800 + 0x400 * mem_id);
global_regs = (struct src_general_regs *)(ulong)SRC_GLOBAL_RBASE;
/* Allow NS to set it */
setbits_le32(&mix_regs->authen_ctrl, BIT(9));
clrsetbits_le32(&mix_regs->psw_ack_ctrl[0], BIT(28), BIT(29));
/* mix reset will be held until boot core write this bit to 1 */
setbits_le32(&global_regs->scr, scr);
/* Enable mem in Low power auto sequence */
setbits_le32(&mem_regs->mem_ctrl, BIT(2));
/* Set the power down state */
val = readl(&mix_regs->func_stat);
if (val & SRC_MIX_SLICE_FUNC_STAT_PSW_STAT) {
/* The mix is default power off, power down it to make PDN_SFT bit
* aligned with FUNC STAT
*/
setbits_le32(&mix_regs->slice_sw_ctrl, BIT(31));
val = readl(&mix_regs->func_stat);
/* Since PSW_STAT is 1, can't be used for power off status (SW_CTRL BIT31 set)) */
/* Check the MEM STAT change to ensure SSAR is completed */
while (!(val & SRC_MIX_SLICE_FUNC_STAT_MEM_STAT))
val = readl(&mix_regs->func_stat);
/* wait few ipg clock cycles to ensure FSM done and power off status is correct */
/* About 5 cycles at 24Mhz, 1us is enough */
udelay(1);
} else {
/* The mix is default power on, Do mix power cycle */
setbits_le32(&mix_regs->slice_sw_ctrl, BIT(31));
val = readl(&mix_regs->func_stat);
while (!(val & SRC_MIX_SLICE_FUNC_STAT_PSW_STAT))
val = readl(&mix_regs->func_stat);
}
/* power on */
clrbits_le32(&mix_regs->slice_sw_ctrl, BIT(31));
val = readl(&mix_regs->func_stat);
while (val & SRC_MIX_SLICE_FUNC_STAT_ISO_STAT)
val = readl(&mix_regs->func_stat);
return 0;
}
void disable_isolation(void)
{
struct src_general_regs *global_regs = (struct src_general_regs *)(ulong)SRC_GLOBAL_RBASE;
/* clear isolation for usbphy, dsi, csi*/
writel(0x0, &global_regs->sp_iso_ctrl);
}
void soc_power_init(void)
{
mix_power_init(MIX_PD_MEDIAMIX);
mix_power_init(MIX_PD_MLMIX);
disable_isolation();
}
bool m33_is_rom_kicked(void)
{
struct blk_ctrl_s_aonmix_regs *s_regs =
(struct blk_ctrl_s_aonmix_regs *)BLK_CTRL_S_ANOMIX_BASE_ADDR;
if (!(readl(&s_regs->m33_cfg) & BIT(2)))
return true;
return false;
}
int m33_prepare(void)
{
struct src_mix_slice_regs *mix_regs =
(struct src_mix_slice_regs *)(ulong)(SRC_IPS_BASE_ADDR + 0x400 * (SRC_MIX_CM33 + 1));
struct src_general_regs *global_regs =
(struct src_general_regs *)(ulong)SRC_GLOBAL_RBASE;
struct blk_ctrl_s_aonmix_regs *s_regs =
(struct blk_ctrl_s_aonmix_regs *)BLK_CTRL_S_ANOMIX_BASE_ADDR;
u32 val;
if (m33_is_rom_kicked())
return -EPERM;
/* Release reset of M33 */
setbits_le32(&global_regs->scr, BIT(0));
/* Check the reset released in M33 MIX func stat */
val = readl(&mix_regs->func_stat);
while (!(val & SRC_MIX_SLICE_FUNC_STAT_RST_STAT))
val = readl(&mix_regs->func_stat);
/* Release Sentinel TROUT */
ahab_release_m33_trout();
/* Mask WDOG1 IRQ from A55, we use it for M33 reset */
setbits_le32(&s_regs->ca55_irq_mask[1], BIT(6));
/* Turn on WDOG1 clock */
ccm_lpcg_on(CCGR_WDG1, 1);
/* Set sentinel LP handshake for M33 reset */
setbits_le32(&s_regs->lp_handshake[0], BIT(6));
/* Clear M33 TCM for ECC */
memset((void *)(ulong)0x201e0000, 0, 0x40000);
return 0;
}
int psci_sysreset_get_status(struct udevice *dev, char *buf, int size)
{
static const char *reset_cause[] = {
"POR ",
"JTAG ",
"IPP USER ",
"WDOG1 ",
"WDOG2 ",
"WDOG3 ",
"WDOG4 ",
"WDOG5 ",
"TEMPSENSE ",
"CSU ",
"JTAG_SW ",
"M33_REQ ",
"M33_LOCKUP ",
"UNK ",
"UNK ",
"UNK "
};
struct src_general_regs *src = (struct src_general_regs *)SRC_GLOBAL_RBASE;
u32 srsr;
u32 i;
int res;
srsr = readl(&src->gpr[0]);
for (i = ARRAY_SIZE(reset_cause); i > 0; i--) {
if (srsr & (BIT(i - 1)))
break;
}
res = snprintf(buf, size, "Reset Status: %s\n", i ? reset_cause[i - 1] : "unknown reset");
if (res < 0) {
dev_err(dev, "Could not write reset status message (err = %d)\n", res);
return -EIO;
}
return 0;
}