diff options
| -rw-r--r-- | drivers/clk/clk-stm32f4.c | 13 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu-sun8i-a33.c | 11 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_common.c | 49 | ||||
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_common.h | 12 |
5 files changed, 84 insertions, 3 deletions
diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c index ab609a76706f..cf9449b3dbd9 100644 --- a/drivers/clk/clk-stm32f4.c +++ b/drivers/clk/clk-stm32f4.c @@ -429,6 +429,13 @@ static const struct clk_div_table pll_divp_table[] = { { 0, 2 }, { 1, 4 }, { 2, 6 }, { 3, 8 }, { 0 } }; +static const struct clk_div_table pll_divq_table[] = { + { 2, 2 }, { 3, 3 }, { 4, 4 }, { 5, 5 }, { 6, 6 }, { 7, 7 }, + { 8, 8 }, { 9, 9 }, { 10, 10 }, { 11, 11 }, { 12, 12 }, { 13, 13 }, + { 14, 14 }, { 15, 15 }, + { 0 } +}; + static const struct clk_div_table pll_divr_table[] = { { 2, 2 }, { 3, 3 }, { 4, 4 }, { 5, 5 }, { 6, 6 }, { 7, 7 }, { 0 } }; @@ -496,9 +503,9 @@ struct stm32f4_div_data { #define MAX_PLL_DIV 3 static const struct stm32f4_div_data div_data[MAX_PLL_DIV] = { - { 16, 2, 0, pll_divp_table }, - { 24, 4, CLK_DIVIDER_ONE_BASED, NULL }, - { 28, 3, 0, pll_divr_table }, + { 16, 2, 0, pll_divp_table }, + { 24, 4, 0, pll_divq_table }, + { 28, 3, 0, pll_divr_table }, }; struct stm32f4_pll_data { diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig index 72109d2cf41b..1c2357301017 100644 --- a/drivers/clk/sunxi-ng/Kconfig +++ b/drivers/clk/sunxi-ng/Kconfig @@ -1,6 +1,7 @@ config SUNXI_CCU bool "Clock support for Allwinner SoCs" depends on ARCH_SUNXI || COMPILE_TEST + select RESET_CONTROLLER default ARCH_SUNXI if SUNXI_CCU @@ -135,6 +136,7 @@ config SUN8I_V3S_CCU config SUN9I_A80_CCU bool "Support for the Allwinner A80 CCU" select SUNXI_CCU_DIV + select SUNXI_CCU_MULT select SUNXI_CCU_GATE select SUNXI_CCU_NKMP select SUNXI_CCU_NM diff --git a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c index a7b3c08ed0e2..2c69b631967a 100644 --- a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c +++ b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c @@ -752,6 +752,13 @@ static const struct sunxi_ccu_desc sun8i_a33_ccu_desc = { .num_resets = ARRAY_SIZE(sun8i_a33_ccu_resets), }; +static struct ccu_pll_nb sun8i_a33_pll_cpu_nb = { + .common = &pll_cpux_clk.common, + /* copy from pll_cpux_clk */ + .enable = BIT(31), + .lock = BIT(28), +}; + static struct ccu_mux_nb sun8i_a33_cpu_nb = { .common = &cpux_clk.common, .cm = &cpux_clk.mux, @@ -783,6 +790,10 @@ static void __init sun8i_a33_ccu_setup(struct device_node *node) sunxi_ccu_probe(node, reg, &sun8i_a33_ccu_desc); + /* Gate then ungate PLL CPU after any rate changes */ + ccu_pll_notifier_register(&sun8i_a33_pll_cpu_nb); + + /* Reparent CPU during PLL CPU rate changes */ ccu_mux_notifier_register(pll_cpux_clk.common.hw.clk, &sun8i_a33_cpu_nb); } diff --git a/drivers/clk/sunxi-ng/ccu_common.c b/drivers/clk/sunxi-ng/ccu_common.c index 8a47bafd7890..9d8724715a43 100644 --- a/drivers/clk/sunxi-ng/ccu_common.c +++ b/drivers/clk/sunxi-ng/ccu_common.c @@ -14,11 +14,13 @@ * GNU General Public License for more details. */ +#include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/iopoll.h> #include <linux/slab.h> #include "ccu_common.h" +#include "ccu_gate.h" #include "ccu_reset.h" static DEFINE_SPINLOCK(ccu_lock); @@ -39,6 +41,53 @@ void ccu_helper_wait_for_lock(struct ccu_common *common, u32 lock) WARN_ON(readl_relaxed_poll_timeout(addr, reg, reg & lock, 100, 70000)); } +/* + * This clock notifier is called when the frequency of a PLL clock is + * changed. In common PLL designs, changes to the dividers take effect + * almost immediately, while changes to the multipliers (implemented + * as dividers in the feedback loop) take a few cycles to work into + * the feedback loop for the PLL to stablize. + * + * Sometimes when the PLL clock rate is changed, the decrease in the + * divider is too much for the decrease in the multiplier to catch up. + * The PLL clock rate will spike, and in some cases, might lock up + * completely. + * + * This notifier callback will gate and then ungate the clock, + * effectively resetting it, so it proceeds to work. Care must be + * taken to reparent consumers to other temporary clocks during the + * rate change, and that this notifier callback must be the first + * to be registered. + */ +static int ccu_pll_notifier_cb(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct ccu_pll_nb *pll = to_ccu_pll_nb(nb); + int ret = 0; + + if (event != POST_RATE_CHANGE) + goto out; + + ccu_gate_helper_disable(pll->common, pll->enable); + + ret = ccu_gate_helper_enable(pll->common, pll->enable); + if (ret) + goto out; + + ccu_helper_wait_for_lock(pll->common, pll->lock); + +out: + return notifier_from_errno(ret); +} + +int ccu_pll_notifier_register(struct ccu_pll_nb *pll_nb) +{ + pll_nb->clk_nb.notifier_call = ccu_pll_notifier_cb; + + return clk_notifier_register(pll_nb->common->hw.clk, + &pll_nb->clk_nb); +} + int sunxi_ccu_probe(struct device_node *node, void __iomem *reg, const struct sunxi_ccu_desc *desc) { diff --git a/drivers/clk/sunxi-ng/ccu_common.h b/drivers/clk/sunxi-ng/ccu_common.h index 73d81dc58fc5..d6fdd7a789aa 100644 --- a/drivers/clk/sunxi-ng/ccu_common.h +++ b/drivers/clk/sunxi-ng/ccu_common.h @@ -83,6 +83,18 @@ struct sunxi_ccu_desc { void ccu_helper_wait_for_lock(struct ccu_common *common, u32 lock); +struct ccu_pll_nb { + struct notifier_block clk_nb; + struct ccu_common *common; + + u32 enable; + u32 lock; +}; + +#define to_ccu_pll_nb(_nb) container_of(_nb, struct ccu_pll_nb, clk_nb) + +int ccu_pll_notifier_register(struct ccu_pll_nb *pll_nb); + int sunxi_ccu_probe(struct device_node *node, void __iomem *reg, const struct sunxi_ccu_desc *desc); |