diff options
| -rw-r--r-- | drivers/clk/clk-stm32f4.c | 137 |
1 files changed, 136 insertions, 1 deletions
diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c index 6427e0fdde59..cbc814868508 100644 --- a/drivers/clk/clk-stm32f4.c +++ b/drivers/clk/clk-stm32f4.c @@ -126,7 +126,7 @@ static const struct stm32f4_gate_data stm32f4_gates[] __initconst = { { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" }, }; -enum { SYSTICK, FCLK, CLK_LSI, CLK_LSE, END_PRIMARY_CLK }; +enum { SYSTICK, FCLK, CLK_LSI, CLK_LSE, CLK_HSE_RTC, CLK_RTC, END_PRIMARY_CLK }; /* * MAX_CLKS is the maximum value in the enumeration below plus the combined * hweight of stm32f42xx_gate_map (plus one). @@ -313,6 +313,15 @@ static inline void enable_power_domain_write_protection(void) regmap_update_bits(pdrm, 0x00, (1 << 8), (0 << 8)); } +static inline void sofware_reset_backup_domain(void) +{ + unsigned long val; + + val = readl(base + STM32F4_RCC_BDCR); + writel(val | BIT(16), base + STM32F4_RCC_BDCR); + writel(val & ~BIT(16), base + STM32F4_RCC_BDCR); +} + struct stm32_rgate { struct clk_gate gate; u8 bit_rdy_idx; @@ -391,6 +400,111 @@ static struct clk_hw *clk_register_rgate(struct device *dev, const char *name, return hw; } +static int cclk_gate_enable(struct clk_hw *hw) +{ + int ret; + + disable_power_domain_write_protection(); + + ret = clk_gate_ops.enable(hw); + + enable_power_domain_write_protection(); + + return ret; +} + +static void cclk_gate_disable(struct clk_hw *hw) +{ + disable_power_domain_write_protection(); + + clk_gate_ops.disable(hw); + + enable_power_domain_write_protection(); +} + +static int cclk_gate_is_enabled(struct clk_hw *hw) +{ + return clk_gate_ops.is_enabled(hw); +} + +static const struct clk_ops cclk_gate_ops = { + .enable = cclk_gate_enable, + .disable = cclk_gate_disable, + .is_enabled = cclk_gate_is_enabled, +}; + +static u8 cclk_mux_get_parent(struct clk_hw *hw) +{ + return clk_mux_ops.get_parent(hw); +} + +static int cclk_mux_set_parent(struct clk_hw *hw, u8 index) +{ + int ret; + + disable_power_domain_write_protection(); + + sofware_reset_backup_domain(); + + ret = clk_mux_ops.set_parent(hw, index); + + enable_power_domain_write_protection(); + + return ret; +} + +static const struct clk_ops cclk_mux_ops = { + .get_parent = cclk_mux_get_parent, + .set_parent = cclk_mux_set_parent, +}; + +static struct clk_hw *stm32_register_cclk(struct device *dev, const char *name, + const char * const *parent_names, int num_parents, + void __iomem *reg, u8 bit_idx, u8 shift, unsigned long flags, + spinlock_t *lock) +{ + struct clk_hw *hw; + struct clk_gate *gate; + struct clk_mux *mux; + + gate = kzalloc(sizeof(*gate), GFP_KERNEL); + if (!gate) { + hw = ERR_PTR(-EINVAL); + goto fail; + } + + mux = kzalloc(sizeof(*mux), GFP_KERNEL); + if (!mux) { + kfree(gate); + hw = ERR_PTR(-EINVAL); + goto fail; + } + + gate->reg = reg; + gate->bit_idx = bit_idx; + gate->flags = 0; + gate->lock = lock; + + mux->reg = reg; + mux->shift = shift; + mux->mask = 3; + mux->flags = 0; + + hw = clk_hw_register_composite(dev, name, parent_names, num_parents, + &mux->hw, &cclk_mux_ops, + NULL, NULL, + &gate->hw, &cclk_gate_ops, + flags); + + if (IS_ERR(hw)) { + kfree(gate); + kfree(mux); + } + +fail: + return hw; +} + static const char *sys_parents[] __initdata = { "hsi", NULL, "pll" }; static const struct clk_div_table ahb_div_table[] = { @@ -407,6 +521,10 @@ static const struct clk_div_table apb_div_table[] = { { 0 }, }; +static const char *rtc_parents[4] = { + "no-clock", "lse", "lsi", "hse-rtc" +}; + static void __init stm32f4_rcc_init(struct device_node *np) { const char *hse_clk; @@ -492,6 +610,23 @@ static void __init stm32f4_rcc_init(struct device_node *np) goto fail; } + clks[CLK_HSE_RTC] = clk_hw_register_divider(NULL, "hse-rtc", "clk-hse", + 0, base + STM32F4_RCC_CFGR, 16, 5, 0, + &stm32f4_clk_lock); + + if (IS_ERR(clks[CLK_HSE_RTC])) { + pr_err("Unable to register hse-rtc clock\n"); + goto fail; + } + + clks[CLK_RTC] = stm32_register_cclk(NULL, "rtc", rtc_parents, 4, + base + STM32F4_RCC_BDCR, 15, 8, 0, &stm32f4_clk_lock); + + if (IS_ERR(clks[CLK_RTC])) { + pr_err("Unable to register rtc clock\n"); + goto fail; + } + of_clk_add_hw_provider(np, stm32f4_rcc_lookup_clk, NULL); return; fail: |