clk: stm32f4: Add PLL_I2S & PLL_SAI for STM32F429/469 boards
authorGabriel Fernandez <gabriel.fernandez@st.com>
Tue, 13 Dec 2016 14:20:13 +0000 (15:20 +0100)
committerStephen Boyd <sboyd@codeaurora.org>
Thu, 22 Dec 2016 00:09:08 +0000 (16:09 -0800)
This patch introduces PLL_I2S and PLL_SAI.
Vco clock of these PLLs can be modify by DT (only n multiplicator,
m divider is still fixed by the boot-loader).
Each PLL has 3 dividers. PLL should be off when we modify the rate.

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Acked-by: Rob Herring <robh@kernel.org>
[sboyd@codeaurora.org: Mark stm32f4_pll_div_ops static]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
drivers/clk/clk-stm32f4.c

index 5eb05dbf59b84d27d79106adeb7405d15de1433a..d9dc79b91731e75b8283829d506546314954349a 100644 (file)
 #include <linux/regmap.h>
 #include <linux/mfd/syscon.h>
 
+/*
+ * Include list of clocks wich are not derived from system clock (SYSCLOCK)
+ * The index of these clocks is the secondary index of DT bindings
+ *
+ */
+#include <dt-bindings/clock/stm32fx-clock.h>
+
+#define STM32F4_RCC_CR                 0x00
 #define STM32F4_RCC_PLLCFGR            0x04
 #define STM32F4_RCC_CFGR               0x08
 #define STM32F4_RCC_AHB1ENR            0x30
@@ -37,6 +45,8 @@
 #define STM32F4_RCC_APB2ENR            0x44
 #define STM32F4_RCC_BDCR               0x70
 #define STM32F4_RCC_CSR                        0x74
+#define STM32F4_RCC_PLLI2SCFGR         0x84
+#define STM32F4_RCC_PLLSAICFGR         0x88
 
 struct stm32f4_gate_data {
        u8      offset;
@@ -208,8 +218,6 @@ static const struct stm32f4_gate_data stm32f469_gates[] __initconst = {
        { STM32F4_RCC_APB2ENR, 26,      "ltdc",         "apb2_div" },
 };
 
-enum { SYSTICK, FCLK, CLK_LSI, CLK_LSE, CLK_HSE_RTC, CLK_RTC, END_PRIMARY_CLK };
-
 /*
  * This bitmask tells us which bit offsets (0..192) on STM32F4[23]xxx
  * have gate bits associated with them. Its combined hweight is 71.
@@ -324,23 +332,312 @@ static struct clk *clk_register_apb_mul(struct device *dev, const char *name,
        return clk;
 }
 
-/*
- * Decode current PLL state and (statically) model the state we inherit from
- * the bootloader.
- */
-static void stm32f4_rcc_register_pll(const char *hse_clk, const char *hsi_clk)
+enum {
+       PLL,
+       PLL_I2S,
+       PLL_SAI,
+};
+
+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_divr_table[] = {
+       { 2, 2 }, { 3, 3 }, { 4, 4 }, { 5, 5 }, { 6, 6 }, { 7, 7 }, { 0 }
+};
+
+struct stm32f4_pll {
+       spinlock_t *lock;
+       struct  clk_gate gate;
+       u8 offset;
+       u8 bit_rdy_idx;
+       u8 status;
+       u8 n_start;
+};
+
+#define to_stm32f4_pll(_gate) container_of(_gate, struct stm32f4_pll, gate)
+
+struct stm32f4_vco_data {
+       const char *vco_name;
+       u8 offset;
+       u8 bit_idx;
+       u8 bit_rdy_idx;
+};
+
+static const struct stm32f4_vco_data  vco_data[] = {
+       { "vco",     STM32F4_RCC_PLLCFGR,    24, 25 },
+       { "vco-i2s", STM32F4_RCC_PLLI2SCFGR, 26, 27 },
+       { "vco-sai", STM32F4_RCC_PLLSAICFGR, 28, 29 },
+};
+
+struct stm32f4_div_data {
+       u8 shift;
+       u8 width;
+       u8 flag_div;
+       const struct clk_div_table *div_table;
+};
+
+#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  },
+};
+
+struct stm32f4_pll_data {
+       u8 pll_num;
+       u8 n_start;
+       const char *div_name[MAX_PLL_DIV];
+};
+
+static const struct stm32f4_pll_data stm32f429_pll[MAX_PLL_DIV] = {
+       { PLL,     192, { "pll", "pll48",    NULL       } },
+       { PLL_I2S, 192, { NULL,  "plli2s-q", "plli2s-r" } },
+       { PLL_SAI,  49, { NULL,  "pllsai-q", "pllsai-r" } },
+};
+
+static const struct stm32f4_pll_data stm32f469_pll[MAX_PLL_DIV] = {
+       { PLL,     50, { "pll",      "pll-q",    NULL       } },
+       { PLL_I2S, 50, { "plli2s-p", "plli2s-q", "plli2s-r" } },
+       { PLL_SAI, 50, { "pllsai-p", "pllsai-q", "pllsai-r" } },
+};
+
+static int stm32f4_pll_is_enabled(struct clk_hw *hw)
+{
+       return clk_gate_ops.is_enabled(hw);
+}
+
+static int stm32f4_pll_enable(struct clk_hw *hw)
+{
+       struct clk_gate *gate = to_clk_gate(hw);
+       struct stm32f4_pll *pll = to_stm32f4_pll(gate);
+       int ret = 0;
+       unsigned long reg;
+
+       ret = clk_gate_ops.enable(hw);
+
+       ret = readl_relaxed_poll_timeout_atomic(base + STM32F4_RCC_CR, reg,
+                       reg & (1 << pll->bit_rdy_idx), 0, 10000);
+
+       return ret;
+}
+
+static void stm32f4_pll_disable(struct clk_hw *hw)
+{
+       clk_gate_ops.disable(hw);
+}
+
+static unsigned long stm32f4_pll_recalc(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       struct clk_gate *gate = to_clk_gate(hw);
+       struct stm32f4_pll *pll = to_stm32f4_pll(gate);
+       unsigned long n;
+
+       n = (readl(base + pll->offset) >> 6) & 0x1ff;
+
+       return parent_rate * n;
+}
+
+static long stm32f4_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+               unsigned long *prate)
+{
+       struct clk_gate *gate = to_clk_gate(hw);
+       struct stm32f4_pll *pll = to_stm32f4_pll(gate);
+       unsigned long n;
+
+       n = rate / *prate;
+
+       if (n < pll->n_start)
+               n = pll->n_start;
+       else if (n > 432)
+               n = 432;
+
+       return *prate * n;
+}
+
+static int stm32f4_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+                               unsigned long parent_rate)
+{
+       struct clk_gate *gate = to_clk_gate(hw);
+       struct stm32f4_pll *pll = to_stm32f4_pll(gate);
+
+       unsigned long n;
+       unsigned long val;
+       int pll_state;
+
+       pll_state = stm32f4_pll_is_enabled(hw);
+
+       if (pll_state)
+               stm32f4_pll_disable(hw);
+
+       n = rate  / parent_rate;
+
+       val = readl(base + pll->offset) & ~(0x1ff << 6);
+
+       writel(val | ((n & 0x1ff) <<  6), base + pll->offset);
+
+       if (pll_state)
+               stm32f4_pll_enable(hw);
+
+       return 0;
+}
+
+static const struct clk_ops stm32f4_pll_gate_ops = {
+       .enable         = stm32f4_pll_enable,
+       .disable        = stm32f4_pll_disable,
+       .is_enabled     = stm32f4_pll_is_enabled,
+       .recalc_rate    = stm32f4_pll_recalc,
+       .round_rate     = stm32f4_pll_round_rate,
+       .set_rate       = stm32f4_pll_set_rate,
+};
+
+struct stm32f4_pll_div {
+       struct clk_divider div;
+       struct clk_hw *hw_pll;
+};
+
+#define to_pll_div_clk(_div) container_of(_div, struct stm32f4_pll_div, div)
+
+static unsigned long stm32f4_pll_div_recalc_rate(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       return clk_divider_ops.recalc_rate(hw, parent_rate);
+}
+
+static long stm32f4_pll_div_round_rate(struct clk_hw *hw, unsigned long rate,
+                               unsigned long *prate)
+{
+       return clk_divider_ops.round_rate(hw, rate, prate);
+}
+
+static int stm32f4_pll_div_set_rate(struct clk_hw *hw, unsigned long rate,
+                               unsigned long parent_rate)
+{
+       int pll_state, ret;
+
+       struct clk_divider *div = to_clk_divider(hw);
+       struct stm32f4_pll_div *pll_div = to_pll_div_clk(div);
+
+       pll_state = stm32f4_pll_is_enabled(pll_div->hw_pll);
+
+       if (pll_state)
+               stm32f4_pll_disable(pll_div->hw_pll);
+
+       ret = clk_divider_ops.set_rate(hw, rate, parent_rate);
+
+       if (pll_state)
+               stm32f4_pll_enable(pll_div->hw_pll);
+
+       return ret;
+}
+
+static const struct clk_ops stm32f4_pll_div_ops = {
+       .recalc_rate = stm32f4_pll_div_recalc_rate,
+       .round_rate = stm32f4_pll_div_round_rate,
+       .set_rate = stm32f4_pll_div_set_rate,
+};
+
+static struct clk_hw *clk_register_pll_div(const char *name,
+               const char *parent_name, unsigned long flags,
+               void __iomem *reg, u8 shift, u8 width,
+               u8 clk_divider_flags, const struct clk_div_table *table,
+               struct clk_hw *pll_hw, spinlock_t *lock)
 {
-       unsigned long pllcfgr = readl(base + STM32F4_RCC_PLLCFGR);
+       struct stm32f4_pll_div *pll_div;
+       struct clk_hw *hw;
+       struct clk_init_data init;
+       int ret;
+
+       /* allocate the divider */
+       pll_div = kzalloc(sizeof(*pll_div), GFP_KERNEL);
+       if (!pll_div)
+               return ERR_PTR(-ENOMEM);
+
+       init.name = name;
+       init.ops = &stm32f4_pll_div_ops;
+       init.flags = flags;
+       init.parent_names = (parent_name ? &parent_name : NULL);
+       init.num_parents = (parent_name ? 1 : 0);
+
+       /* struct clk_divider assignments */
+       pll_div->div.reg = reg;
+       pll_div->div.shift = shift;
+       pll_div->div.width = width;
+       pll_div->div.flags = clk_divider_flags;
+       pll_div->div.lock = lock;
+       pll_div->div.table = table;
+       pll_div->div.hw.init = &init;
+
+       pll_div->hw_pll = pll_hw;
+
+       /* register the clock */
+       hw = &pll_div->div.hw;
+       ret = clk_hw_register(NULL, hw);
+       if (ret) {
+               kfree(pll_div);
+               hw = ERR_PTR(ret);
+       }
+
+       return hw;
+}
+
+static struct clk_hw *stm32f4_rcc_register_pll(const char *pllsrc,
+               const struct stm32f4_pll_data *data,  spinlock_t *lock)
+{
+       struct stm32f4_pll *pll;
+       struct clk_init_data init = { NULL };
+       void __iomem *reg;
+       struct clk_hw *pll_hw;
+       int ret;
+       int i;
+       const struct stm32f4_vco_data *vco;
+
+
+       pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+       if (!pll)
+               return ERR_PTR(-ENOMEM);
+
+       vco = &vco_data[data->pll_num];
+
+       init.name = vco->vco_name;
+       init.ops = &stm32f4_pll_gate_ops;
+       init.flags = CLK_SET_RATE_GATE;
+       init.parent_names = &pllsrc;
+       init.num_parents = 1;
+
+       pll->gate.lock = lock;
+       pll->gate.reg = base + STM32F4_RCC_CR;
+       pll->gate.bit_idx = vco->bit_idx;
+       pll->gate.hw.init = &init;
+
+       pll->offset = vco->offset;
+       pll->n_start = data->n_start;
+       pll->bit_rdy_idx = vco->bit_rdy_idx;
+       pll->status = (readl(base + STM32F4_RCC_CR) >> vco->bit_idx) & 0x1;
 
-       unsigned long pllm   = pllcfgr & 0x3f;
-       unsigned long plln   = (pllcfgr >> 6) & 0x1ff;
-       unsigned long pllp   = BIT(((pllcfgr >> 16) & 3) + 1);
-       const char   *pllsrc = pllcfgr & BIT(22) ? hse_clk : hsi_clk;
-       unsigned long pllq   = (pllcfgr >> 24) & 0xf;
+       reg = base + pll->offset;
 
-       clk_register_fixed_factor(NULL, "vco", pllsrc, 0, plln, pllm);
-       clk_register_fixed_factor(NULL, "pll", "vco", 0, 1, pllp);
-       clk_register_fixed_factor(NULL, "pll48", "vco", 0, 1, pllq);
+       pll_hw = &pll->gate.hw;
+       ret = clk_hw_register(NULL, pll_hw);
+       if (ret) {
+               kfree(pll);
+               return ERR_PTR(ret);
+       }
+
+       for (i = 0; i < MAX_PLL_DIV; i++)
+               if (data->div_name[i])
+                       clk_register_pll_div(data->div_name[i],
+                                       vco->vco_name,
+                                       0,
+                                       reg,
+                                       div_data[i].shift,
+                                       div_data[i].width,
+                                       div_data[i].flag_div,
+                                       div_data[i].div_table,
+                                       pll_hw,
+                                       lock);
+       return pll_hw;
 }
 
 /*
@@ -615,18 +912,21 @@ struct stm32f4_clk_data {
        const struct stm32f4_gate_data *gates_data;
        const u64 *gates_map;
        int gates_num;
+       const struct stm32f4_pll_data *pll_data;
 };
 
 static const struct stm32f4_clk_data stm32f429_clk_data = {
        .gates_data     = stm32f429_gates,
        .gates_map      = stm32f42xx_gate_map,
        .gates_num      = ARRAY_SIZE(stm32f429_gates),
+       .pll_data       = stm32f429_pll,
 };
 
 static const struct stm32f4_clk_data stm32f469_clk_data = {
        .gates_data     = stm32f469_gates,
        .gates_map      = stm32f46xx_gate_map,
        .gates_num      = ARRAY_SIZE(stm32f469_gates),
+       .pll_data       = stm32f469_pll,
 };
 
 static const struct of_device_id stm32f4_of_match[] = {
@@ -647,6 +947,9 @@ static void __init stm32f4_rcc_init(struct device_node *np)
        int n;
        const struct of_device_id *match;
        const struct stm32f4_clk_data *data;
+       unsigned long pllcfgr;
+       const char *pllsrc;
+       unsigned long pllm;
 
        base = of_iomap(np, 0);
        if (!base) {
@@ -677,7 +980,21 @@ static void __init stm32f4_rcc_init(struct device_node *np)
 
        clk_register_fixed_rate_with_accuracy(NULL, "hsi", NULL, 0,
                        16000000, 160000);
-       stm32f4_rcc_register_pll(hse_clk, "hsi");
+       pllcfgr = readl(base + STM32F4_RCC_PLLCFGR);
+       pllsrc = pllcfgr & BIT(22) ? hse_clk : "hsi";
+       pllm = pllcfgr & 0x3f;
+
+       clk_hw_register_fixed_factor(NULL, "vco_in", pllsrc,
+                                              0, 1, pllm);
+
+       stm32f4_rcc_register_pll("vco_in", &data->pll_data[0],
+                       &stm32f4_clk_lock);
+
+       clks[PLL_VCO_I2S] = stm32f4_rcc_register_pll("vco_in",
+                       &data->pll_data[1], &stm32f4_clk_lock);
+
+       clks[PLL_VCO_SAI] = stm32f4_rcc_register_pll("vco_in",
+                       &data->pll_data[2], &stm32f4_clk_lock);
 
        sys_parents[1] = hse_clk;
        clk_register_mux_table(