[PATCH v3 2/9] clk: stm32f4: Add PLL_I2S & PLL_SAI for STM32F429/469 boards
From: gabriel.fernandez
Date: Thu Dec 01 2016 - 10:30:10 EST
From: Gabriel Fernandez <gabriel.fernandez@xxxxxx>
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@xxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
---
drivers/clk/clk-stm32f4.c | 351 +++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 334 insertions(+), 17 deletions(-)
diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
index 5eb05db..c2b62cc 100644
--- a/drivers/clk/clk-stm32f4.c
+++ b/drivers/clk/clk-stm32f4.c
@@ -28,6 +28,14 @@
#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/stm32f4-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 @@ struct stm32f4_gate_data {
{ 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;
+}
+
+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(
--
1.9.1