From b3b02eac33eddda88992962d920b46348bb086da Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Thu, 8 Jun 2017 02:36:47 +0200 Subject: [PATCH] clk: at91: Add sama5d2 suspend/resume On sama5d2, VDD core maybe be cut while in suspend. This means registers will be lost. Ensure they are saved and restored properly. Signed-off-by: Alexandre Belloni Acked-by: Nicolas Ferre Signed-off-by: Stephen Boyd --- drivers/clk/at91/clk-generated.c | 2 + drivers/clk/at91/clk-peripheral.c | 4 +- drivers/clk/at91/pmc.c | 129 ++++++++++++++++++++++++++++++ drivers/clk/at91/pmc.h | 6 ++ 4 files changed, 140 insertions(+), 1 deletion(-) diff --git a/drivers/clk/at91/clk-generated.c b/drivers/clk/at91/clk-generated.c index 07c8f701e51c..f0b7ae904ce2 100644 --- a/drivers/clk/at91/clk-generated.c +++ b/drivers/clk/at91/clk-generated.c @@ -266,6 +266,8 @@ at91_clk_register_generated(struct regmap *regmap, spinlock_t *lock, if (ret) { kfree(gck); hw = ERR_PTR(ret); + } else { + pmc_register_id(id); } return hw; diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c index dc29fd979d3f..770118369230 100644 --- a/drivers/clk/at91/clk-peripheral.c +++ b/drivers/clk/at91/clk-peripheral.c @@ -367,8 +367,10 @@ at91_clk_register_sam9x5_peripheral(struct regmap *regmap, spinlock_t *lock, if (ret) { kfree(periph); hw = ERR_PTR(ret); - } else + } else { clk_sam9x5_peripheral_autodiv(periph); + pmc_register_id(id); + } return hw; } diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c index 526df5ba042d..775af473fe11 100644 --- a/drivers/clk/at91/pmc.c +++ b/drivers/clk/at91/pmc.c @@ -13,12 +13,16 @@ #include #include #include +#include #include +#include #include #include "pmc.h" +#define PMC_MAX_IDS 128 + int of_at91_get_clk_range(struct device_node *np, const char *propname, struct clk_range *range) { @@ -41,3 +45,128 @@ int of_at91_get_clk_range(struct device_node *np, const char *propname, return 0; } EXPORT_SYMBOL_GPL(of_at91_get_clk_range); + +#ifdef CONFIG_PM +static struct regmap *pmcreg; + +static u8 registered_ids[PMC_MAX_IDS]; + +static struct +{ + u32 scsr; + u32 pcsr0; + u32 uckr; + u32 mor; + u32 mcfr; + u32 pllar; + u32 mckr; + u32 usb; + u32 imr; + u32 pcsr1; + u32 pcr[PMC_MAX_IDS]; + u32 audio_pll0; + u32 audio_pll1; +} pmc_cache; + +void pmc_register_id(u8 id) +{ + int i; + + for (i = 0; i < PMC_MAX_IDS; i++) { + if (registered_ids[i] == 0) { + registered_ids[i] = id; + break; + } + if (registered_ids[i] == id) + break; + } +} + +static int pmc_suspend(void) +{ + int i; + + regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.scsr); + regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0); + regmap_read(pmcreg, AT91_CKGR_UCKR, &pmc_cache.uckr); + regmap_read(pmcreg, AT91_CKGR_MOR, &pmc_cache.mor); + regmap_read(pmcreg, AT91_CKGR_MCFR, &pmc_cache.mcfr); + regmap_read(pmcreg, AT91_CKGR_PLLAR, &pmc_cache.pllar); + regmap_read(pmcreg, AT91_PMC_MCKR, &pmc_cache.mckr); + regmap_read(pmcreg, AT91_PMC_USB, &pmc_cache.usb); + regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.imr); + regmap_read(pmcreg, AT91_PMC_PCSR1, &pmc_cache.pcsr1); + + for (i = 0; registered_ids[i]; i++) { + regmap_write(pmcreg, AT91_PMC_PCR, + (registered_ids[i] & AT91_PMC_PCR_PID_MASK)); + regmap_read(pmcreg, AT91_PMC_PCR, + &pmc_cache.pcr[registered_ids[i]]); + } + + return 0; +} + +static void pmc_resume(void) +{ + int i, ret = 0; + u32 tmp; + + regmap_read(pmcreg, AT91_PMC_MCKR, &tmp); + if (pmc_cache.mckr != tmp) + pr_warn("MCKR was not configured properly by the firmware\n"); + regmap_read(pmcreg, AT91_CKGR_PLLAR, &tmp); + if (pmc_cache.pllar != tmp) + pr_warn("PLLAR was not configured properly by the firmware\n"); + + regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.scsr); + regmap_write(pmcreg, AT91_PMC_PCER, pmc_cache.pcsr0); + regmap_write(pmcreg, AT91_CKGR_UCKR, pmc_cache.uckr); + regmap_write(pmcreg, AT91_CKGR_MOR, pmc_cache.mor); + regmap_write(pmcreg, AT91_CKGR_MCFR, pmc_cache.mcfr); + regmap_write(pmcreg, AT91_PMC_USB, pmc_cache.usb); + regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.imr); + regmap_write(pmcreg, AT91_PMC_PCER1, pmc_cache.pcsr1); + + for (i = 0; registered_ids[i]; i++) { + regmap_write(pmcreg, AT91_PMC_PCR, + pmc_cache.pcr[registered_ids[i]] | + AT91_PMC_PCR_CMD); + } + + if (pmc_cache.uckr & AT91_PMC_UPLLEN) { + ret = regmap_read_poll_timeout(pmcreg, AT91_PMC_SR, tmp, + !(tmp & AT91_PMC_LOCKU), + 10, 5000); + if (ret) + pr_crit("USB PLL didn't lock when resuming\n"); + } +} + +static struct syscore_ops pmc_syscore_ops = { + .suspend = pmc_suspend, + .resume = pmc_resume, +}; + +static const struct of_device_id sama5d2_pmc_dt_ids[] = { + { .compatible = "atmel,sama5d2-pmc" }, + { /* sentinel */ } +}; + +static int __init pmc_register_ops(void) +{ + struct device_node *np; + + np = of_find_matching_node(NULL, sama5d2_pmc_dt_ids); + + pmcreg = syscon_node_to_regmap(np); + if (IS_ERR(pmcreg)) + return PTR_ERR(pmcreg); + + register_syscore_ops(&pmc_syscore_ops); + + return 0; +} +/* This has to happen before arch_initcall because of the tcb_clksrc driver */ +postcore_initcall(pmc_register_ops); +#endif diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h index 5771fff0ee3f..858e8ef7e8db 100644 --- a/drivers/clk/at91/pmc.h +++ b/drivers/clk/at91/pmc.h @@ -29,4 +29,10 @@ struct clk_range { int of_at91_get_clk_range(struct device_node *np, const char *propname, struct clk_range *range); +#ifdef CONFIG_PM +void pmc_register_id(u8 id); +#else +static inline void pmc_register_id(u8 id) {} +#endif + #endif /* __PMC_H_ */ -- 2.20.1