| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * OMAP1 reset support |
| 4 | */ |
| 5 | #include <linux/kernel.h> |
| 6 | #include <linux/io.h> |
| 7 | #include <linux/reboot.h> |
| 8 | |
| 9 | #include "hardware.h" |
| 10 | #include "iomap.h" |
| 11 | #include "common.h" |
| 12 | |
| 13 | /* ARM_SYSST bit shifts related to SoC reset sources */ |
| 14 | #define ARM_SYSST_POR_SHIFT 5 |
| 15 | #define ARM_SYSST_EXT_RST_SHIFT 4 |
| 16 | #define ARM_SYSST_ARM_WDRST_SHIFT 2 |
| 17 | #define ARM_SYSST_GLOB_SWRST_SHIFT 1 |
| 18 | |
| 19 | /* Standardized reset source bits (across all OMAP SoCs) */ |
| 20 | #define OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT 0 |
| 21 | #define OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT 1 |
| 22 | #define OMAP_MPU_WD_RST_SRC_ID_SHIFT 3 |
| 23 | #define OMAP_EXTWARM_RST_SRC_ID_SHIFT 5 |
| 24 | |
| 25 | |
| 26 | void omap1_restart(enum reboot_mode mode, const char *cmd) |
| 27 | { |
| 28 | /* |
| 29 | * Workaround for 5912/1611b bug mentioned in sprz209d.pdf p. 28 |
| 30 | * "Global Software Reset Affects Traffic Controller Frequency". |
| 31 | */ |
| 32 | if (cpu_is_omap5912()) { |
| 33 | omap_writew(v: omap_readw(DPLL_CTL) & ~(1 << 4), DPLL_CTL); |
| 34 | omap_writew(v: 0x8, ARM_RSTCT1); |
| 35 | } |
| 36 | |
| 37 | omap_writew(v: 1, ARM_RSTCT1); |
| 38 | } |
| 39 | |
| 40 | /** |
| 41 | * omap1_get_reset_sources - return the source of the SoC's last reset |
| 42 | * |
| 43 | * Returns bits that represent the last reset source for the SoC. The |
| 44 | * format is standardized across OMAPs for use by the OMAP watchdog. |
| 45 | */ |
| 46 | u32 omap1_get_reset_sources(void) |
| 47 | { |
| 48 | u32 ret = 0; |
| 49 | u16 rs; |
| 50 | |
| 51 | rs = __raw_readw(OMAP1_IO_ADDRESS(ARM_SYSST)); |
| 52 | |
| 53 | if (rs & (1 << ARM_SYSST_POR_SHIFT)) |
| 54 | ret |= 1 << OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT; |
| 55 | if (rs & (1 << ARM_SYSST_EXT_RST_SHIFT)) |
| 56 | ret |= 1 << OMAP_EXTWARM_RST_SRC_ID_SHIFT; |
| 57 | if (rs & (1 << ARM_SYSST_ARM_WDRST_SHIFT)) |
| 58 | ret |= 1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT; |
| 59 | if (rs & (1 << ARM_SYSST_GLOB_SWRST_SHIFT)) |
| 60 | ret |= 1 << OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT; |
| 61 | |
| 62 | return ret; |
| 63 | } |
| 64 |