From 24a0f5c539f944248cbb2e3502830dcb7fd2a96e Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Tue, 27 Sep 2016 12:29:50 +0200 Subject: [PATCH] ARM: at91: pm: Add sama5d2 backup mode The sama5d2 has a mode were it is possible to cut power to the SoC while keeping the RAM in self refresh. Resuming from that mode needs support in the firmware/bootloader. Signed-off-by: Alexandre Belloni Acked-by: Wenyou Yang --- arch/arm/mach-at91/generic.h | 2 + arch/arm/mach-at91/pm.c | 109 ++++++++++++++++++++++++++- arch/arm/mach-at91/pm.h | 4 + arch/arm/mach-at91/pm_data-offsets.c | 3 + arch/arm/mach-at91/pm_suspend.S | 73 +++++++++++++----- arch/arm/mach-at91/sama5.c | 19 ++++- 6 files changed, 187 insertions(+), 23 deletions(-) diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h index f1ead0f13c19..e2bd17237964 100644 --- a/arch/arm/mach-at91/generic.h +++ b/arch/arm/mach-at91/generic.h @@ -15,10 +15,12 @@ extern void __init at91rm9200_pm_init(void); extern void __init at91sam9_pm_init(void); extern void __init sama5_pm_init(void); +extern void __init sama5d2_pm_init(void); #else static inline void __init at91rm9200_pm_init(void) { } static inline void __init at91sam9_pm_init(void) { } static inline void __init sama5_pm_init(void) { } +static inline void __init sama5d2_pm_init(void) { } #endif #endif /* _AT91_GENERIC_H */ diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index 2cd27c830ab6..d138d19fa9f0 100644 --- a/arch/arm/mach-at91/pm.c +++ b/arch/arm/mach-at91/pm.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "generic.h" #include "pm.h" @@ -58,6 +59,14 @@ static int at91_pm_valid_state(suspend_state_t state) } } +static int canary = 0xA5A5A5A5; + +static struct at91_pm_bu { + int suspended; + unsigned long reserved; + phys_addr_t canary; + phys_addr_t resume; +} *pm_bu; static suspend_state_t target_state; @@ -123,15 +132,39 @@ static void (*at91_suspend_sram_fn)(struct at91_pm_data *); extern void at91_pm_suspend_in_sram(struct at91_pm_data *pm_data); extern u32 at91_pm_suspend_in_sram_sz; -static void at91_pm_suspend(suspend_state_t state) +static int at91_suspend_finish(unsigned long val) { - pm_data.mode = (state == PM_SUSPEND_MEM) ? AT91_PM_SLOW_CLOCK : 0; - flush_cache_all(); outer_disable(); at91_suspend_sram_fn(&pm_data); + return 0; +} + +static void at91_pm_suspend(suspend_state_t state) +{ + if (pm_data.deepest_state == AT91_PM_BACKUP) + if (state == PM_SUSPEND_MEM) + pm_data.mode = AT91_PM_BACKUP; + else + pm_data.mode = AT91_PM_SLOW_CLOCK; + else + pm_data.mode = (state == PM_SUSPEND_MEM) ? AT91_PM_SLOW_CLOCK : 0; + + if (pm_data.mode == AT91_PM_BACKUP) { + pm_bu->suspended = 1; + + cpu_suspend(0, at91_suspend_finish); + + /* The SRAM is lost between suspend cycles */ + at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn, + &at91_pm_suspend_in_sram, + at91_pm_suspend_in_sram_sz); + } else { + at91_suspend_finish(0); + } + outer_resume(); } @@ -436,6 +469,70 @@ static void __init at91_pm_sram_init(void) &at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz); } +static void __init at91_pm_backup_init(void) +{ + struct gen_pool *sram_pool; + struct device_node *np; + struct platform_device *pdev = NULL; + + pm_bu = NULL; + + np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-shdwc"); + if (!np) { + pr_warn("%s: failed to find shdwc!\n", __func__); + return; + } + + pm_data.shdwc = of_iomap(np, 0); + of_node_put(np); + + np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-sfrbu"); + if (!np) { + pr_warn("%s: failed to find sfrbu!\n", __func__); + goto sfrbu_fail; + } + + pm_data.sfrbu = of_iomap(np, 0); + of_node_put(np); + pm_bu = NULL; + + np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-securam"); + if (!np) + goto securam_fail; + + pdev = of_find_device_by_node(np); + of_node_put(np); + if (!pdev) { + pr_warn("%s: failed to find securam device!\n", __func__); + goto securam_fail; + } + + sram_pool = gen_pool_get(&pdev->dev, NULL); + if (!sram_pool) { + pr_warn("%s: securam pool unavailable!\n", __func__); + goto securam_fail; + } + + pm_bu = (void *)gen_pool_alloc(sram_pool, sizeof(struct at91_pm_bu)); + if (!pm_bu) { + pr_warn("%s: unable to alloc securam!\n", __func__); + goto securam_fail; + } + + pm_bu->suspended = 0; + pm_bu->canary = virt_to_phys(&canary); + pm_bu->resume = virt_to_phys(cpu_resume); + + return; + +sfrbu_fail: + iounmap(pm_data.shdwc); + pm_data.shdwc = NULL; +securam_fail: + iounmap(pm_data.sfrbu); + pm_data.sfrbu = NULL; +} + struct pmc_info { unsigned long uhp_udp_mask; }; @@ -510,3 +607,9 @@ void __init sama5_pm_init(void) at91_dt_ramc(); at91_pm_init(NULL); } + +void __init sama5d2_pm_init(void) +{ + at91_pm_backup_init(); + sama5_pm_init(); +} diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h index fc0f7d048187..d9c6612ef62f 100644 --- a/arch/arm/mach-at91/pm.h +++ b/arch/arm/mach-at91/pm.h @@ -22,6 +22,7 @@ #define AT91_MEMCTRL_DDRSDR 2 #define AT91_PM_SLOW_CLOCK 0x01 +#define AT91_PM_BACKUP 0x02 #ifndef __ASSEMBLY__ struct at91_pm_data { @@ -30,6 +31,9 @@ struct at91_pm_data { unsigned long uhp_udp_mask; unsigned int memctrl; unsigned int mode; + void __iomem *shdwc; + void __iomem *sfrbu; + unsigned int deepest_state; }; #endif diff --git a/arch/arm/mach-at91/pm_data-offsets.c b/arch/arm/mach-at91/pm_data-offsets.c index 30302cb16df0..c0a73e62b725 100644 --- a/arch/arm/mach-at91/pm_data-offsets.c +++ b/arch/arm/mach-at91/pm_data-offsets.c @@ -9,5 +9,8 @@ int main(void) DEFINE(PM_DATA_RAMC1, offsetof(struct at91_pm_data, ramc[1])); DEFINE(PM_DATA_MEMCTRL, offsetof(struct at91_pm_data, memctrl)); DEFINE(PM_DATA_MODE, offsetof(struct at91_pm_data, mode)); + DEFINE(PM_DATA_SHDWC, offsetof(struct at91_pm_data, shdwc)); + DEFINE(PM_DATA_SFRBU, offsetof(struct at91_pm_data, sfrbu)); + return 0; } diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S index 96781daa671a..daca91feea6a 100644 --- a/arch/arm/mach-at91/pm_suspend.S +++ b/arch/arm/mach-at91/pm_suspend.S @@ -97,15 +97,61 @@ ENTRY(at91_pm_suspend_in_sram) str tmp1, .memtype ldr tmp1, [r0, #PM_DATA_MODE] str tmp1, .pm_mode + /* Both ldrne below are here to preload their address in the TLB */ + ldr tmp1, [r0, #PM_DATA_SHDWC] + str tmp1, .shdwc + cmp tmp1, #0 + ldrne tmp2, [tmp1, #0] + ldr tmp1, [r0, #PM_DATA_SFRBU] + str tmp1, .sfr + cmp tmp1, #0 + ldrne tmp2, [tmp1, #0x10] /* Active the self-refresh mode */ mov r0, #SRAMC_SELF_FRESH_ACTIVE bl at91_sramc_self_refresh ldr r0, .pm_mode - tst r0, #AT91_PM_SLOW_CLOCK - beq skip_disable_main_clock + cmp r0, #AT91_PM_SLOW_CLOCK + beq slow_clock + cmp r0, #AT91_PM_BACKUP + beq backup_mode + /* Wait for interrupt */ + ldr pmc, .pmc_base + at91_cpu_idle + b exit_suspend + +slow_clock: + bl at91_slowck_mode + b exit_suspend +backup_mode: + bl at91_backup_mode + b exit_suspend + +exit_suspend: + /* Exit the self-refresh mode */ + mov r0, #SRAMC_SELF_FRESH_EXIT + bl at91_sramc_self_refresh + + /* Restore registers, and return */ + ldmfd sp!, {r4 - r12, pc} +ENDPROC(at91_pm_suspend_in_sram) + +ENTRY(at91_backup_mode) + /*BUMEN*/ + ldr r0, .sfr + mov tmp1, #0x1 + str tmp1, [r0, #0x10] + + /* Shutdown */ + ldr r0, .shdwc + mov tmp1, #0xA5000000 + add tmp1, tmp1, #0x1 + str tmp1, [r0, #0] +ENDPROC(at91_backup_mode) + +ENTRY(at91_slowck_mode) ldr pmc, .pmc_base /* Save Master clock setting */ @@ -134,18 +180,9 @@ ENTRY(at91_pm_suspend_in_sram) orr tmp1, tmp1, #AT91_PMC_KEY str tmp1, [pmc, #AT91_CKGR_MOR] -skip_disable_main_clock: - ldr pmc, .pmc_base - /* Wait for interrupt */ at91_cpu_idle - ldr r0, .pm_mode - tst r0, #AT91_PM_SLOW_CLOCK - beq skip_enable_main_clock - - ldr pmc, .pmc_base - /* Turn on the main oscillator */ ldr tmp1, [pmc, #AT91_CKGR_MOR] orr tmp1, tmp1, #AT91_PMC_MOSCEN @@ -174,14 +211,8 @@ skip_disable_main_clock: wait_mckrdy -skip_enable_main_clock: - /* Exit the self-refresh mode */ - mov r0, #SRAMC_SELF_FRESH_EXIT - bl at91_sramc_self_refresh - - /* Restore registers, and return */ - ldmfd sp!, {r4 - r12, pc} -ENDPROC(at91_pm_suspend_in_sram) + mov pc, lr +ENDPROC(at91_slowck_mode) /* * void at91_sramc_self_refresh(unsigned int is_active) @@ -314,6 +345,10 @@ ENDPROC(at91_sramc_self_refresh) .word 0 .sramc1_base: .word 0 +.shdwc: + .word 0 +.sfr: + .word 0 .memtype: .word 0 .pm_mode: diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c index 6d157d0ead8e..3d0bf95a56ae 100644 --- a/arch/arm/mach-at91/sama5.c +++ b/arch/arm/mach-at91/sama5.c @@ -34,7 +34,6 @@ DT_MACHINE_START(sama5_dt, "Atmel SAMA5") MACHINE_END static const char *const sama5_alt_dt_board_compat[] __initconst = { - "atmel,sama5d2", "atmel,sama5d4", NULL }; @@ -45,3 +44,21 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5") .dt_compat = sama5_alt_dt_board_compat, .l2c_aux_mask = ~0UL, MACHINE_END + +static void __init sama5d2_init(void) +{ + of_platform_default_populate(NULL, NULL, NULL); + sama5d2_pm_init(); +} + +static const char *const sama5d2_compat[] __initconst = { + "atmel,sama5d2", + NULL +}; + +DT_MACHINE_START(sama5d2, "Atmel SAMA5") + /* Maintainer: Atmel */ + .init_machine = sama5d2_init, + .dt_compat = sama5d2_compat, + .l2c_aux_mask = ~0UL, +MACHINE_END -- 2.20.1