Subject: [PATCH 2/4] clk: ep93xx: add DT support for Cirrus EP93xx

From: Nikita Shubin <[email protected]>

Rewrite EP93xx clock driver located in arch/arm/mach-ep93xx/clock.c
trying to do everything the device tree way:

- provide clock acces via of
- drop clk_hw_register_clkdev
- drop init code and use module_auxiliary_driver

Co-developed-by: Alexander Sverdlin <[email protected]>
Signed-off-by: Alexander Sverdlin <[email protected]>
Signed-off-by: Nikita Shubin <[email protected]>
---
drivers/clk/Kconfig | 8 +
drivers/clk/Makefile | 1 +
drivers/clk/clk-ep93xx.c | 840 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 849 insertions(+)

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 50af5fc7f570..0f0351251285 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -218,6 +218,14 @@ config COMMON_CLK_EN7523
This driver provides the fixed clocks and gates present on Airoha
ARM silicon.

+config COMMON_CLK_EP93XX
+ bool "Clock driver for Cirrus Logic ep93xx SoC"
+ depends on ARCH_EP93XX || COMPILE_TEST
+ select MFD_SYSCON
+ select REGMAP
+ help
+ This driver supports the SoC clocks on the Cirrus Logic ep93xx.
+
config COMMON_CLK_FSL_FLEXSPI
tristate "Clock driver for FlexSPI on Layerscape SoCs"
depends on ARCH_LAYERSCAPE || COMPILE_TEST
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 14fa8d4ecc1f..bfb8827deda7 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_COMMON_CLK_CDCE706) += clk-cdce706.o
obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o
obj-$(CONFIG_ARCH_CLPS711X) += clk-clps711x.o
obj-$(CONFIG_COMMON_CLK_CS2000_CP) += clk-cs2000-cp.o
+obj-$(CONFIG_COMMON_CLK_EP93XX) += clk-ep93xx.o
obj-$(CONFIG_ARCH_SPARX5) += clk-sparx5.o
obj-$(CONFIG_COMMON_CLK_EN7523) += clk-en7523.o
obj-$(CONFIG_COMMON_CLK_FIXED_MMIO) += clk-fixed-mmio.o
diff --git a/drivers/clk/clk-ep93xx.c b/drivers/clk/clk-ep93xx.c
new file mode 100644
index 000000000000..601acb4402be
--- /dev/null
+++ b/drivers/clk/clk-ep93xx.c
@@ -0,0 +1,840 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Clock control for Cirrus EP93xx chips.
+ * Copyright (C) 2021 Nikita Shubin <[email protected]>
+ *
+ * Based on a rewrite of arch/arm/mach-ep93xx/clock.c:
+ * Copyright (C) 2006 Lennert Buytenhek <[email protected]>
+ */
+#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
+
+#include <linux/bits.h>
+#include <linux/cleanup.h>
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/math.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/spinlock.h>
+#include <linux/sys_soc.h>
+
+#include <linux/soc/cirrus/ep93xx.h>
+#include <dt-bindings/clock/cirrus,ep9301-syscon.h>
+
+#include <asm/div64.h>
+
+#define EP93XX_EXT_CLK_RATE 14745600
+#define EP93XX_EXT_RTC_RATE 32768
+
+#define EP93XX_SYSCON_POWER_STATE 0x00
+#define EP93XX_SYSCON_PWRCNT 0x04
+#define EP93XX_SYSCON_PWRCNT_UARTBAUD BIT(29)
+#define EP93XX_SYSCON_PWRCNT_USH_EN 28
+#define EP93XX_SYSCON_PWRCNT_DMA_M2M1 27
+#define EP93XX_SYSCON_PWRCNT_DMA_M2M0 26
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P8 25
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P9 24
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P6 23
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P7 22
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P4 21
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P5 20
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P2 19
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P3 18
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P0 17
+#define EP93XX_SYSCON_PWRCNT_DMA_M2P1 16
+#define EP93XX_SYSCON_CLKSET1 0x20
+#define EP93XX_SYSCON_CLKSET1_NBYP1 BIT(23)
+#define EP93XX_SYSCON_CLKSET2 0x24
+#define EP93XX_SYSCON_CLKSET2_NBYP2 BIT(19)
+#define EP93XX_SYSCON_CLKSET2_PLL2_EN BIT(18)
+#define EP93XX_SYSCON_DEVCFG 0x80
+#define EP93XX_SYSCON_DEVCFG_U3EN 24
+#define EP93XX_SYSCON_DEVCFG_U2EN 20
+#define EP93XX_SYSCON_DEVCFG_U1EN 18
+#define EP93XX_SYSCON_VIDCLKDIV 0x84
+#define EP93XX_SYSCON_CLKDIV_ENABLE 15
+#define EP93XX_SYSCON_CLKDIV_ESEL BIT(14)
+#define EP93XX_SYSCON_CLKDIV_PSEL BIT(13)
+#define EP93XX_SYSCON_CLKDIV_MASK GENMASK(14, 13)
+#define EP93XX_SYSCON_CLKDIV_PDIV_SHIFT 8
+#define EP93XX_SYSCON_I2SCLKDIV 0x8c
+#define EP93XX_SYSCON_I2SCLKDIV_SENA 31
+#define EP93XX_SYSCON_I2SCLKDIV_ORIDE BIT(29)
+#define EP93XX_SYSCON_I2SCLKDIV_SPOL BIT(19)
+#define EP93XX_SYSCON_KEYTCHCLKDIV 0x90
+#define EP93XX_SYSCON_KEYTCHCLKDIV_TSEN 31
+#define EP93XX_SYSCON_KEYTCHCLKDIV_ADIV 16
+#define EP93XX_SYSCON_KEYTCHCLKDIV_KEN 15
+#define EP93XX_SYSCON_KEYTCHCLKDIV_KDIV 0
+#define EP93XX_SYSCON_CHIPID 0x94
+#define EP93XX_SYSCON_CHIPID_ID 0x9213
+
+static const char adc_divisors[] = { 16, 4 };
+static const char sclk_divisors[] = { 2, 4 };
+static const char lrclk_divisors[] = { 32, 64, 128 };
+
+struct ep93xx_clk {
+ struct clk_hw hw;
+ u16 idx;
+ u16 reg;
+ u32 mask;
+ u8 bit_idx;
+ u8 shift;
+ u8 width;
+ u8 num_div;
+ const char *div;
+};
+
+struct ep93xx_clk_priv {
+ spinlock_t lock;
+ struct ep93xx_regmap_adev *aux_dev;
+ struct device *dev;
+ void __iomem *base;
+ struct regmap *map;
+ struct clk_hw *fixed[21];
+ struct ep93xx_clk reg[];
+};
+
+static struct ep93xx_clk *ep93xx_clk_from(struct clk_hw *hw)
+{
+ return container_of(hw, struct ep93xx_clk, hw);
+}
+
+static struct ep93xx_clk_priv *ep93xx_priv_from(struct ep93xx_clk *clk)
+{
+ return container_of(clk, struct ep93xx_clk_priv, reg[clk->idx]);
+}
+
+static void ep93xx_clk_write(struct ep93xx_clk_priv *priv, unsigned int reg, unsigned int val)
+{
+ struct ep93xx_regmap_adev *aux = priv->aux_dev;
+
+ aux->write(aux->map, aux->lock, reg, val);
+}
+
+static int ep93xx_clk_is_enabled(struct clk_hw *hw)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+
+ regmap_read(priv->map, clk->reg, &val);
+
+ return !!(val & BIT(clk->bit_idx));
+}
+
+static int ep93xx_clk_enable(struct clk_hw *hw)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+
+ guard(spinlock_irqsave)(&priv->lock);
+
+ regmap_read(priv->map, clk->reg, &val);
+ val |= BIT(clk->bit_idx);
+
+ ep93xx_clk_write(priv, clk->reg, val);
+
+ return 0;
+}
+
+static void ep93xx_clk_disable(struct clk_hw *hw)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+
+ guard(spinlock_irqsave)(&priv->lock);
+
+ regmap_read(priv->map, clk->reg, &val);
+ val &= ~BIT(clk->bit_idx);
+
+ ep93xx_clk_write(priv, clk->reg, val);
+}
+
+static const struct clk_ops clk_ep93xx_gate_ops = {
+ .enable = ep93xx_clk_enable,
+ .disable = ep93xx_clk_disable,
+ .is_enabled = ep93xx_clk_is_enabled,
+};
+
+static int ep93xx_clk_register_gate(struct ep93xx_clk *clk,
+ const char *name,
+ struct clk_parent_data *parent_data,
+ unsigned long flags,
+ unsigned int reg,
+ u8 bit_idx)
+{
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ struct clk_init_data init = { };
+
+ init.name = name;
+ init.ops = &clk_ep93xx_gate_ops;
+ init.flags = flags;
+ init.parent_data = parent_data;
+ init.num_parents = 1;
+
+ clk->reg = reg;
+ clk->bit_idx = bit_idx;
+ clk->hw.init = &init;
+
+ return devm_clk_hw_register(priv->dev, &clk->hw);
+}
+
+static u8 ep93xx_mux_get_parent(struct clk_hw *hw)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+
+ regmap_read(priv->map, clk->reg, &val);
+
+ val &= EP93XX_SYSCON_CLKDIV_MASK;
+
+ switch (val) {
+ case EP93XX_SYSCON_CLKDIV_ESEL:
+ return 1; /* PLL1 */
+ case EP93XX_SYSCON_CLKDIV_MASK:
+ return 2; /* PLL2 */
+ default:
+ return 0; /* XTALI */
+ };
+}
+
+static int ep93xx_mux_set_parent_lock(struct clk_hw *hw, u8 index)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+
+ if (index >= 3)
+ return -EINVAL;
+
+ guard(spinlock_irqsave)(&priv->lock);
+
+ regmap_read(priv->map, clk->reg, &val);
+ val &= ~(EP93XX_SYSCON_CLKDIV_MASK);
+ val |= index > 0 ? EP93XX_SYSCON_CLKDIV_ESEL : 0;
+ val |= index > 1 ? EP93XX_SYSCON_CLKDIV_PSEL : 0;
+
+ ep93xx_clk_write(priv, clk->reg, val);
+
+ return 0;
+}
+
+static bool is_best(unsigned long rate, unsigned long now,
+ unsigned long best)
+{
+ return abs_diff(rate, now) < abs_diff(rate, best);
+}
+
+static int ep93xx_mux_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ unsigned long best_rate = 0, actual_rate, mclk_rate;
+ unsigned long rate = req->rate;
+ struct clk_hw *parent_best = NULL;
+ unsigned long parent_rate_best;
+ unsigned long parent_rate;
+ int div, pdiv;
+ unsigned int i;
+
+ /*
+ * Try the two pll's and the external clock,
+ * because the valid predividers are 2, 2.5 and 3, we multiply
+ * all the clocks by 2 to avoid floating point math.
+ *
+ * This is based on the algorithm in the ep93xx raster guide:
+ * http://be-a-maverick.com/en/pubs/appNote/AN269REV1.pdf
+ *
+ */
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+ struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i);
+
+ parent_rate = clk_hw_get_rate(parent);
+ mclk_rate = parent_rate * 2;
+
+ /* Try each predivider value */
+ for (pdiv = 4; pdiv <= 6; pdiv++) {
+ div = DIV_ROUND_CLOSEST(mclk_rate, rate * pdiv);
+ if (!in_range(div, 1, 127))
+ continue;
+
+ actual_rate = DIV_ROUND_CLOSEST(mclk_rate, pdiv * div);
+ if (is_best(rate, actual_rate, best_rate)) {
+ best_rate = actual_rate;
+ parent_rate_best = parent_rate;
+ parent_best = parent;
+ }
+ }
+ }
+
+ if (!parent_best)
+ return -EINVAL;
+
+ req->best_parent_rate = parent_rate_best;
+ req->best_parent_hw = parent_best;
+ req->rate = best_rate;
+
+ return 0;
+}
+
+static unsigned long ep93xx_ddiv_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ unsigned int pdiv, div;
+ u32 val;
+
+ regmap_read(priv->map, clk->reg, &val);
+ pdiv = (val >> EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) & GENMASK(1, 0);
+ div = val & GENMASK(6, 0);
+ if (!div)
+ return 0;
+
+ return DIV_ROUND_CLOSEST(parent_rate * 2, (pdiv + 3) * div);
+}
+
+static int ep93xx_ddiv_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ int pdiv, div, npdiv, ndiv;
+ unsigned long actual_rate, mclk_rate, rate_err = ULONG_MAX;
+ u32 val;
+
+ regmap_read(priv->map, clk->reg, &val);
+ mclk_rate = parent_rate * 2;
+
+ for (pdiv = 4; pdiv <= 6; pdiv++) {
+ div = DIV_ROUND_CLOSEST(mclk_rate, rate * pdiv);
+ if (!in_range(div, 1, 127))
+ continue;
+
+ actual_rate = DIV_ROUND_CLOSEST(mclk_rate, pdiv * div);
+ if (abs(actual_rate - rate) < rate_err) {
+ npdiv = pdiv - 3;
+ ndiv = div;
+ rate_err = abs(actual_rate - rate);
+ }
+ }
+
+ if (rate_err == ULONG_MAX)
+ return -EINVAL;
+
+ /*
+ * Clear old dividers.
+ * Bit 7 is reserved bit in all ClkDiv registers.
+ */
+ val &= ~(GENMASK(9, 0) & ~BIT(7));
+
+ /* Set the new pdiv and div bits for the new clock rate */
+ val |= (npdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | ndiv;
+
+ ep93xx_clk_write(priv, clk->reg, val);
+
+ return 0;
+}
+
+static const struct clk_ops clk_ddiv_ops = {
+ .enable = ep93xx_clk_enable,
+ .disable = ep93xx_clk_disable,
+ .is_enabled = ep93xx_clk_is_enabled,
+ .get_parent = ep93xx_mux_get_parent,
+ .set_parent = ep93xx_mux_set_parent_lock,
+ .determine_rate = ep93xx_mux_determine_rate,
+ .recalc_rate = ep93xx_ddiv_recalc_rate,
+ .set_rate = ep93xx_ddiv_set_rate,
+};
+
+static int clk_hw_register_ddiv(struct ep93xx_clk *clk,
+ const char *name,
+ struct clk_parent_data *parent_data,
+ u8 num_parents,
+ unsigned int reg,
+ u8 bit_idx)
+{
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ struct clk_init_data init = { };
+
+ init.name = name;
+ init.ops = &clk_ddiv_ops;
+ init.flags = 0;
+ init.parent_data = parent_data;
+ init.num_parents = num_parents;
+
+ clk->reg = reg;
+ clk->bit_idx = bit_idx;
+ clk->hw.init = &init;
+
+ return devm_clk_hw_register(priv->dev, &clk->hw);
+}
+
+static unsigned long ep93xx_div_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ u32 val;
+ u8 index;
+
+ regmap_read(priv->map, clk->reg, &val);
+ index = (val & clk->mask) >> clk->shift;
+ if (index > clk->num_div)
+ return 0;
+
+ return DIV_ROUND_CLOSEST(parent_rate, clk->div[index]);
+}
+
+static long ep93xx_div_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ unsigned long best = 0, now;
+ unsigned int i;
+
+ for (i = 0; i < clk->num_div; i++) {
+ if ((rate * clk->div[i]) == *parent_rate)
+ return rate;
+
+ now = DIV_ROUND_CLOSEST(*parent_rate, clk->div[i]);
+ if (!best || is_best(rate, now, best))
+ best = now;
+ }
+
+ return best;
+}
+
+static int ep93xx_div_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct ep93xx_clk *clk = ep93xx_clk_from(hw);
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ unsigned int i;
+ u32 val;
+
+ regmap_read(priv->map, clk->reg, &val);
+ val &= ~clk->mask;
+ for (i = 0; i < clk->num_div; i++)
+ if (rate == DIV_ROUND_CLOSEST(parent_rate, clk->div[i]))
+ break;
+
+ if (i == clk->num_div)
+ return -EINVAL;
+
+ val |= i << clk->shift;
+
+ ep93xx_clk_write(priv, clk->reg, val);
+
+ return 0;
+}
+
+static const struct clk_ops ep93xx_div_ops = {
+ .enable = ep93xx_clk_enable,
+ .disable = ep93xx_clk_disable,
+ .is_enabled = ep93xx_clk_is_enabled,
+ .recalc_rate = ep93xx_div_recalc_rate,
+ .round_rate = ep93xx_div_round_rate,
+ .set_rate = ep93xx_div_set_rate,
+};
+
+static int clk_hw_register_div(struct ep93xx_clk *clk,
+ const char *name,
+ struct clk_parent_data *parent_data,
+ unsigned int reg,
+ u8 enable_bit,
+ u8 shift,
+ u8 width,
+ const char *clk_divisors,
+ u8 num_div)
+{
+ struct ep93xx_clk_priv *priv = ep93xx_priv_from(clk);
+ struct clk_init_data init = { };
+
+ init.name = name;
+ init.ops = &ep93xx_div_ops;
+ init.flags = 0;
+ init.parent_data = parent_data;
+ init.num_parents = 1;
+
+ clk->reg = reg;
+ clk->bit_idx = enable_bit;
+ clk->mask = GENMASK(shift + width - 1, shift);
+ clk->shift = shift;
+ clk->div = clk_divisors;
+ clk->num_div = num_div;
+ clk->hw.init = &init;
+
+ return devm_clk_hw_register(priv->dev, &clk->hw);
+}
+
+struct ep93xx_gate {
+ unsigned int idx;
+ unsigned int bit;
+ const char *name;
+};
+
+static const struct ep93xx_gate ep93xx_uarts[] = {
+ { EP93XX_CLK_UART1, EP93XX_SYSCON_DEVCFG_U1EN, "uart1" },
+ { EP93XX_CLK_UART2, EP93XX_SYSCON_DEVCFG_U2EN, "uart2" },
+ { EP93XX_CLK_UART3, EP93XX_SYSCON_DEVCFG_U3EN, "uart3" },
+};
+
+static int ep93xx_uart_clock_init(struct ep93xx_clk_priv *priv)
+{
+ struct clk_parent_data parent_data = { };
+ unsigned int i, idx, ret, clk_uart_div;
+ struct ep93xx_clk *clk;
+ u32 val;
+
+ regmap_read(priv->map, EP93XX_SYSCON_PWRCNT, &val);
+ if (val & EP93XX_SYSCON_PWRCNT_UARTBAUD)
+ clk_uart_div = 1;
+ else
+ clk_uart_div = 2;
+
+ priv->fixed[EP93XX_CLK_UART] =
+ clk_hw_register_fixed_factor(NULL, "uart", "xtali", 0, 1, clk_uart_div);
+ parent_data.hw = priv->fixed[EP93XX_CLK_UART];
+
+ /* parenting uart gate clocks to uart clock */
+ for (i = 0; i < ARRAY_SIZE(ep93xx_uarts); i++) {
+ idx = ep93xx_uarts[i].idx - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ ret = ep93xx_clk_register_gate(clk,
+ ep93xx_uarts[i].name,
+ &parent_data, CLK_SET_RATE_PARENT,
+ EP93XX_SYSCON_DEVCFG,
+ ep93xx_uarts[i].bit);
+ if (ret)
+ return dev_err_probe(priv->dev, ret,
+ "failed to register uart[%d] clock\n", i);
+ }
+
+ return 0;
+}
+
+static const struct ep93xx_gate ep93xx_dmas[] = {
+ { EP93XX_CLK_M2M0, EP93XX_SYSCON_PWRCNT_DMA_M2M0, "m2m0" },
+ { EP93XX_CLK_M2M1, EP93XX_SYSCON_PWRCNT_DMA_M2M1, "m2m1" },
+ { EP93XX_CLK_M2P0, EP93XX_SYSCON_PWRCNT_DMA_M2P0, "m2p0" },
+ { EP93XX_CLK_M2P1, EP93XX_SYSCON_PWRCNT_DMA_M2P1, "m2p1" },
+ { EP93XX_CLK_M2P2, EP93XX_SYSCON_PWRCNT_DMA_M2P2, "m2p2" },
+ { EP93XX_CLK_M2P3, EP93XX_SYSCON_PWRCNT_DMA_M2P3, "m2p3" },
+ { EP93XX_CLK_M2P4, EP93XX_SYSCON_PWRCNT_DMA_M2P4, "m2p4" },
+ { EP93XX_CLK_M2P5, EP93XX_SYSCON_PWRCNT_DMA_M2P5, "m2p5" },
+ { EP93XX_CLK_M2P6, EP93XX_SYSCON_PWRCNT_DMA_M2P6, "m2p6" },
+ { EP93XX_CLK_M2P7, EP93XX_SYSCON_PWRCNT_DMA_M2P7, "m2p7" },
+ { EP93XX_CLK_M2P8, EP93XX_SYSCON_PWRCNT_DMA_M2P8, "m2p8" },
+ { EP93XX_CLK_M2P9, EP93XX_SYSCON_PWRCNT_DMA_M2P9, "m2p9" },
+};
+
+static int ep93xx_dma_clock_init(struct ep93xx_clk_priv *priv)
+{
+ struct clk_parent_data parent_data = { };
+ unsigned int i, idx;
+
+ parent_data.hw = priv->fixed[EP93XX_CLK_HCLK];
+ for (i = 0; i < ARRAY_SIZE(ep93xx_dmas); i++) {
+ idx = ep93xx_dmas[i].idx;
+ priv->fixed[idx] = devm_clk_hw_register_gate_parent_data(priv->dev,
+ ep93xx_dmas[i].name,
+ &parent_data, 0,
+ priv->base + EP93XX_SYSCON_PWRCNT,
+ ep93xx_dmas[i].bit,
+ 0,
+ &priv->lock);
+ if (IS_ERR(priv->fixed[idx]))
+ return PTR_ERR(priv->fixed[idx]);
+ }
+
+ return 0;
+}
+
+static struct clk_hw *of_clk_ep93xx_get(struct of_phandle_args *clkspec, void *data)
+{
+ struct ep93xx_clk_priv *priv = data;
+ unsigned int idx = clkspec->args[0];
+
+ if (idx < EP93XX_CLK_UART1)
+ return priv->fixed[idx];
+
+ if (idx <= EP93XX_CLK_I2S_LRCLK)
+ return &priv->reg[idx - EP93XX_CLK_UART1].hw;
+
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS
+ */
+static unsigned long calc_pll_rate(u64 rate, u32 config_word)
+{
+ rate *= ((config_word >> 11) & GENMASK(4, 0)) + 1; /* X1FBD */
+ rate *= ((config_word >> 5) & GENMASK(5, 0)) + 1; /* X2FBD */
+ do_div(rate, (config_word & GENMASK(4, 0)) + 1); /* X2IPD */
+ rate >>= (config_word >> 16) & GENMASK(1, 0); /* PS */
+
+ return rate;
+}
+
+static const struct soc_device_attribute ep93xx_soc_table[] = {
+ { .revision = "E2", .data = (void *)1 },
+ { /* sentinel */ }
+};
+
+static int ep93xx_clk_probe(struct auxiliary_device *adev,
+ const struct auxiliary_device_id *id)
+{
+ struct ep93xx_regmap_adev *rdev = to_ep93xx_regmap_adev(adev);
+ unsigned int clk_f_div, clk_h_div, clk_p_div, clk_usb_div;
+ const char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 };
+ const char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 };
+ const char pclk_divisors[] = { 1, 2, 4, 8 };
+ struct clk_parent_data xtali = { .index = 0 };
+ struct clk_parent_data ddiv_pdata[3] = { };
+ unsigned long clk_pll1_rate, clk_pll2_rate, clk_spi_div;
+ const struct soc_device_attribute *match;
+ struct clk_parent_data pdata = {};
+ struct device *dev = &adev->dev;
+ struct ep93xx_clk_priv *priv;
+ struct ep93xx_clk *clk;
+ struct clk_hw *hw, *pll1;
+ unsigned int idx;
+ int ret;
+ u32 value;
+
+ priv = devm_kzalloc(dev, struct_size(priv, reg, 10), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ spin_lock_init(&priv->lock);
+ priv->dev = dev;
+ priv->aux_dev = rdev;
+ priv->map = rdev->map;
+ priv->base = rdev->base;
+
+ /* Determine the bootloader configured pll1 rate */
+ regmap_read(priv->map, EP93XX_SYSCON_CLKSET1, &value);
+
+ if (value & EP93XX_SYSCON_CLKSET1_NBYP1)
+ clk_pll1_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
+ else
+ clk_pll1_rate = EP93XX_EXT_CLK_RATE;
+
+ pll1 = devm_clk_hw_register_fixed_rate(dev, "pll1", "xtali", 0, clk_pll1_rate);
+ if (IS_ERR(pll1))
+ return PTR_ERR(pll1);
+
+ priv->fixed[EP93XX_CLK_PLL1] = pll1;
+
+ /* Initialize the pll1 derived clocks */
+ clk_f_div = fclk_divisors[(value >> 25) & GENMASK(2, 0)];
+ clk_h_div = hclk_divisors[(value >> 20) & GENMASK(2, 0)];
+ clk_p_div = pclk_divisors[(value >> 18) & GENMASK(1, 0)];
+
+ hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "fclk", pll1, 0, 1, clk_f_div);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_FCLK] = hw;
+
+ hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "hclk", pll1, 0, 1, clk_h_div);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_HCLK] = hw;
+
+ hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "pclk", hw, 0, 1, clk_p_div);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_PCLK] = hw;
+
+ /* Determine the bootloader configured pll2 rate */
+ regmap_read(priv->map, EP93XX_SYSCON_CLKSET2, &value);
+ if (!(value & EP93XX_SYSCON_CLKSET2_NBYP2))
+ clk_pll2_rate = EP93XX_EXT_CLK_RATE;
+ else if (value & EP93XX_SYSCON_CLKSET2_PLL2_EN)
+ clk_pll2_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
+ else
+ clk_pll2_rate = 0;
+
+ hw = devm_clk_hw_register_fixed_rate(dev, "pll2", "xtali", 0, clk_pll2_rate);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_PLL2] = hw;
+
+ regmap_read(priv->map, EP93XX_SYSCON_CLKSET2, &value);
+ clk_usb_div = (value >> 28 & GENMASK(3, 0)) + 1;
+ hw = devm_clk_hw_register_fixed_factor(dev, "usb_clk", "pll2", 0, 1, clk_usb_div);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_USB] = hw;
+
+ ret = ep93xx_uart_clock_init(priv);
+ if (ret)
+ return ret;
+
+ ret = ep93xx_dma_clock_init(priv);
+ if (ret)
+ return ret;
+
+ /*
+ * EP93xx SSP clock rate was doubled in version E2. For more information
+ * see section 6 "2x SSP (Synchronous Serial Port) Clock – Revision E2 only":
+ * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
+ */
+ clk_spi_div = 2;
+ match = soc_device_match(ep93xx_soc_table);
+ if (match)
+ clk_spi_div = (unsigned long)match->data;
+
+ hw = devm_clk_hw_register_fixed_factor(dev, "ep93xx-spi.0", "xtali",
+ 0, 1, clk_spi_div);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_SPI] = hw;
+
+ /* PWM clock */
+ hw = devm_clk_hw_register_fixed_factor(dev, "pwm_clk", "xtali", 0, 1, 1);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_PWM] = hw;
+
+ /* USB clock */
+ hw = devm_clk_hw_register_gate(priv->dev, "ohci-platform", "usb_clk",
+ 0, priv->base + EP93XX_SYSCON_PWRCNT,
+ EP93XX_SYSCON_PWRCNT_USH_EN, 0,
+ &priv->lock);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ priv->fixed[EP93XX_CLK_USB] = hw;
+
+ ddiv_pdata[0].index = 0; /* XTALI external clock */
+ ddiv_pdata[1].hw = priv->fixed[EP93XX_CLK_PLL1];
+ ddiv_pdata[2].hw = priv->fixed[EP93XX_CLK_PLL2];
+
+ /* touchscreen/ADC clock */
+ idx = EP93XX_CLK_ADC - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ ret = clk_hw_register_div(clk, "ep93xx-adc", &xtali,
+ EP93XX_SYSCON_KEYTCHCLKDIV,
+ EP93XX_SYSCON_KEYTCHCLKDIV_TSEN,
+ EP93XX_SYSCON_KEYTCHCLKDIV_ADIV,
+ 1,
+ adc_divisors,
+ ARRAY_SIZE(adc_divisors));
+
+
+ /* keypad clock */
+ idx = EP93XX_CLK_KEYPAD - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ ret = clk_hw_register_div(clk, "ep93xx-keypad", &xtali,
+ EP93XX_SYSCON_KEYTCHCLKDIV,
+ EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
+ EP93XX_SYSCON_KEYTCHCLKDIV_KDIV,
+ 1,
+ adc_divisors,
+ ARRAY_SIZE(adc_divisors));
+
+ /*
+ * On reset PDIV and VDIV is set to zero, while PDIV zero
+ * means clock disable, VDIV shouldn't be zero.
+ * So we set both video and i2s dividers to minimum.
+ * ENA - Enable CLK divider.
+ * PDIV - 00 - Disable clock
+ * VDIV - at least 2
+ */
+
+ /* Check and enable video clk registers */
+ regmap_read(priv->map, EP93XX_SYSCON_VIDCLKDIV, &value);
+ value |= BIT(EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
+ ep93xx_clk_write(priv, EP93XX_SYSCON_VIDCLKDIV, value);
+
+ /* Check and enable i2s clk registers */
+ regmap_read(priv->map, EP93XX_SYSCON_I2SCLKDIV, &value);
+ value |= BIT(EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
+
+ /*
+ * Override the SAI_MSTR_CLK_CFG from the I2S block and use the
+ * I2SClkDiv Register settings. LRCLK transitions on the falling SCLK
+ * edge.
+ */
+ value |= EP93XX_SYSCON_I2SCLKDIV_ORIDE | EP93XX_SYSCON_I2SCLKDIV_SPOL;
+ ep93xx_clk_write(priv, EP93XX_SYSCON_I2SCLKDIV, value);
+
+ /* video clk */
+ idx = EP93XX_CLK_VIDEO - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ ret = clk_hw_register_ddiv(clk, "ep93xx-fb",
+ ddiv_pdata, ARRAY_SIZE(ddiv_pdata),
+ EP93XX_SYSCON_VIDCLKDIV,
+ EP93XX_SYSCON_CLKDIV_ENABLE);
+
+ /* i2s clk */
+ idx = EP93XX_CLK_I2S_MCLK - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ ret = clk_hw_register_ddiv(clk, "mclk",
+ ddiv_pdata, ARRAY_SIZE(ddiv_pdata),
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_CLKDIV_ENABLE);
+
+ /* i2s sclk */
+ idx = EP93XX_CLK_I2S_SCLK - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ pdata.hw = &priv->reg[EP93XX_CLK_I2S_MCLK - EP93XX_CLK_UART1].hw;
+ ret = clk_hw_register_div(clk, "sclk", &pdata,
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_I2SCLKDIV_SENA,
+ 16, /* EP93XX_I2SCLKDIV_SDIV_SHIFT */
+ 1, /* EP93XX_I2SCLKDIV_SDIV_WIDTH */
+ sclk_divisors,
+ ARRAY_SIZE(sclk_divisors));
+
+ /* i2s lrclk */
+ idx = EP93XX_CLK_I2S_LRCLK - EP93XX_CLK_UART1;
+ clk = &priv->reg[idx];
+ clk->idx = idx;
+ pdata.hw = &priv->reg[EP93XX_CLK_I2S_SCLK - EP93XX_CLK_UART1].hw;
+ ret = clk_hw_register_div(clk, "lrclk", &pdata,
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_I2SCLKDIV_SENA,
+ 17, /* EP93XX_I2SCLKDIV_LRDIV32_SHIFT */
+ 2, /* EP93XX_I2SCLKDIV_LRDIV32_WIDTH */
+ lrclk_divisors,
+ ARRAY_SIZE(lrclk_divisors));
+
+ /* IrDa clk uses same pattern but no init code presents in original clock driver */
+ return devm_of_clk_add_hw_provider(priv->dev, of_clk_ep93xx_get, priv);
+}
+
+static const struct auxiliary_device_id ep93xx_clk_ids[] = {
+ {
+ .name = "soc_ep93xx.clk-ep93xx",
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(auxiliary, ep93xx_clk_ids);
+
+static struct auxiliary_driver ep93xx_clk_driver = {
+ .probe = ep93xx_clk_probe,
+ .id_table = ep93xx_clk_ids,
+};
+module_auxiliary_driver(ep93xx_clk_driver);

--
2.41.0




2024-04-11 09:43:45

by Stephen Boyd

[permalink] [raw]
Subject: Re: [PATCH 2/4] clk: ep93xx: add DT support for Cirrus EP93xx

Quoting Nikita Shubin via B4 Relay (2024-04-08 01:09:54)
> diff --git a/drivers/clk/clk-ep93xx.c b/drivers/clk/clk-ep93xx.c
> new file mode 100644
> index 000000000000..601acb4402be
> --- /dev/null
> +++ b/drivers/clk/clk-ep93xx.c
> @@ -0,0 +1,840 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Clock control for Cirrus EP93xx chips.
> + * Copyright (C) 2021 Nikita Shubin <[email protected]>
> + *
> + * Based on a rewrite of arch/arm/mach-ep93xx/clock.c:
> + * Copyright (C) 2006 Lennert Buytenhek <[email protected]>
> + */
> +#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
> +
> +#include <linux/bits.h>
> +#include <linux/cleanup.h>
> +#include <linux/clk-provider.h>
> +#include <linux/clk.h>

Is this include used?

> +#include <linux/math.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of_address.h>

Is this include used?

> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/spinlock.h>
> +#include <linux/sys_soc.h>
> +
> +#include <linux/soc/cirrus/ep93xx.h>
> +#include <dt-bindings/clock/cirrus,ep9301-syscon.h>
> +
> +#include <asm/div64.h>


> +
[...]
> +
> +static const struct soc_device_attribute ep93xx_soc_table[] = {
> + { .revision = "E2", .data = (void *)1 },

Can we populate a different named clk auxiliary device instead?
Preferably this table and logic lives in the soc driver that creates the
device for this driver.

> + { /* sentinel */ }
> +};
> +
> +static int ep93xx_clk_probe(struct auxiliary_device *adev,
> + const struct auxiliary_device_id *id)
> +{
> + struct ep93xx_regmap_adev *rdev = to_ep93xx_regmap_adev(adev);
> + unsigned int clk_f_div, clk_h_div, clk_p_div, clk_usb_div;
> + const char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 };
> + const char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 };
> + const char pclk_divisors[] = { 1, 2, 4, 8 };
> + struct clk_parent_data xtali = { .index = 0 };
> + struct clk_parent_data ddiv_pdata[3] = { };
> + unsigned long clk_pll1_rate, clk_pll2_rate, clk_spi_div;
> + const struct soc_device_attribute *match;
> + struct clk_parent_data pdata = {};
> + struct device *dev = &adev->dev;
> + struct ep93xx_clk_priv *priv;
> + struct ep93xx_clk *clk;
> + struct clk_hw *hw, *pll1;
> + unsigned int idx;
> + int ret;
> + u32 value;

Maybe make the pll registration code a sub-function. This is a lot of
local variables.

> +
> + priv = devm_kzalloc(dev, struct_size(priv, reg, 10), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + spin_lock_init(&priv->lock);
> + priv->dev = dev;
> + priv->aux_dev = rdev;
> + priv->map = rdev->map;
> + priv->base = rdev->base;
> +
> + /* Determine the bootloader configured pll1 rate */
> + regmap_read(priv->map, EP93XX_SYSCON_CLKSET1, &value);
> +
> + if (value & EP93XX_SYSCON_CLKSET1_NBYP1)
> + clk_pll1_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
> + else
> + clk_pll1_rate = EP93XX_EXT_CLK_RATE;
> +
> + pll1 = devm_clk_hw_register_fixed_rate(dev, "pll1", "xtali", 0, clk_pll1_rate);
> + if (IS_ERR(pll1))
> + return PTR_ERR(pll1);
> +
> + priv->fixed[EP93XX_CLK_PLL1] = pll1;
> +
> + /* Initialize the pll1 derived clocks */
> + clk_f_div = fclk_divisors[(value >> 25) & GENMASK(2, 0)];
> + clk_h_div = hclk_divisors[(value >> 20) & GENMASK(2, 0)];
> + clk_p_div = pclk_divisors[(value >> 18) & GENMASK(1, 0)];
> +
> + hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "fclk", pll1, 0, 1, clk_f_div);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_FCLK] = hw;
> +
> + hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "hclk", pll1, 0, 1, clk_h_div);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_HCLK] = hw;
> +
> + hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, "pclk", hw, 0, 1, clk_p_div);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_PCLK] = hw;
> +
> + /* Determine the bootloader configured pll2 rate */
> + regmap_read(priv->map, EP93XX_SYSCON_CLKSET2, &value);
> + if (!(value & EP93XX_SYSCON_CLKSET2_NBYP2))
> + clk_pll2_rate = EP93XX_EXT_CLK_RATE;
> + else if (value & EP93XX_SYSCON_CLKSET2_PLL2_EN)
> + clk_pll2_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
> + else
> + clk_pll2_rate = 0;
> +
> + hw = devm_clk_hw_register_fixed_rate(dev, "pll2", "xtali", 0, clk_pll2_rate);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_PLL2] = hw;
> +
> + regmap_read(priv->map, EP93XX_SYSCON_CLKSET2, &value);
> + clk_usb_div = (value >> 28 & GENMASK(3, 0)) + 1;
> + hw = devm_clk_hw_register_fixed_factor(dev, "usb_clk", "pll2", 0, 1, clk_usb_div);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_USB] = hw;
> +
> + ret = ep93xx_uart_clock_init(priv);
> + if (ret)
> + return ret;
> +
> + ret = ep93xx_dma_clock_init(priv);
> + if (ret)
> + return ret;
> +
> + /*
> + * EP93xx SSP clock rate was doubled in version E2. For more information
> + * see section 6 "2x SSP (Synchronous Serial Port) Clock – Revision E2 only":
> + * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
> + */
> + clk_spi_div = 2;
> + match = soc_device_match(ep93xx_soc_table);
> + if (match)
> + clk_spi_div = (unsigned long)match->data;
> +
> + hw = devm_clk_hw_register_fixed_factor(dev, "ep93xx-spi.0", "xtali",
> + 0, 1, clk_spi_div);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_SPI] = hw;
> +
> + /* PWM clock */
> + hw = devm_clk_hw_register_fixed_factor(dev, "pwm_clk", "xtali", 0, 1, 1);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_PWM] = hw;
> +
> + /* USB clock */
> + hw = devm_clk_hw_register_gate(priv->dev, "ohci-platform", "usb_clk",
> + 0, priv->base + EP93XX_SYSCON_PWRCNT,
> + EP93XX_SYSCON_PWRCNT_USH_EN, 0,
> + &priv->lock);
> + if (IS_ERR(hw))
> + return PTR_ERR(hw);
> +
> + priv->fixed[EP93XX_CLK_USB] = hw;
> +
> + ddiv_pdata[0].index = 0; /* XTALI external clock */
> + ddiv_pdata[1].hw = priv->fixed[EP93XX_CLK_PLL1];
> + ddiv_pdata[2].hw = priv->fixed[EP93XX_CLK_PLL2];
> +
> + /* touchscreen/ADC clock */
> + idx = EP93XX_CLK_ADC - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + ret = clk_hw_register_div(clk, "ep93xx-adc", &xtali,

Use devm?

> + EP93XX_SYSCON_KEYTCHCLKDIV,
> + EP93XX_SYSCON_KEYTCHCLKDIV_TSEN,
> + EP93XX_SYSCON_KEYTCHCLKDIV_ADIV,
> + 1,
> + adc_divisors,
> + ARRAY_SIZE(adc_divisors));
> +
> +
> + /* keypad clock */
> + idx = EP93XX_CLK_KEYPAD - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + ret = clk_hw_register_div(clk, "ep93xx-keypad", &xtali,
> + EP93XX_SYSCON_KEYTCHCLKDIV,
> + EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
> + EP93XX_SYSCON_KEYTCHCLKDIV_KDIV,
> + 1,
> + adc_divisors,
> + ARRAY_SIZE(adc_divisors));
> +
> + /*
> + * On reset PDIV and VDIV is set to zero, while PDIV zero
> + * means clock disable, VDIV shouldn't be zero.
> + * So we set both video and i2s dividers to minimum.
> + * ENA - Enable CLK divider.
> + * PDIV - 00 - Disable clock
> + * VDIV - at least 2
> + */
> +
> + /* Check and enable video clk registers */
> + regmap_read(priv->map, EP93XX_SYSCON_VIDCLKDIV, &value);
> + value |= BIT(EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
> + ep93xx_clk_write(priv, EP93XX_SYSCON_VIDCLKDIV, value);
> +
> + /* Check and enable i2s clk registers */
> + regmap_read(priv->map, EP93XX_SYSCON_I2SCLKDIV, &value);
> + value |= BIT(EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
> +
> + /*
> + * Override the SAI_MSTR_CLK_CFG from the I2S block and use the
> + * I2SClkDiv Register settings. LRCLK transitions on the falling SCLK
> + * edge.
> + */
> + value |= EP93XX_SYSCON_I2SCLKDIV_ORIDE | EP93XX_SYSCON_I2SCLKDIV_SPOL;
> + ep93xx_clk_write(priv, EP93XX_SYSCON_I2SCLKDIV, value);
> +
> + /* video clk */
> + idx = EP93XX_CLK_VIDEO - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + ret = clk_hw_register_ddiv(clk, "ep93xx-fb",
> + ddiv_pdata, ARRAY_SIZE(ddiv_pdata),
> + EP93XX_SYSCON_VIDCLKDIV,
> + EP93XX_SYSCON_CLKDIV_ENABLE);
> +
> + /* i2s clk */
> + idx = EP93XX_CLK_I2S_MCLK - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + ret = clk_hw_register_ddiv(clk, "mclk",
> + ddiv_pdata, ARRAY_SIZE(ddiv_pdata),
> + EP93XX_SYSCON_I2SCLKDIV,
> + EP93XX_SYSCON_CLKDIV_ENABLE);
> +
> + /* i2s sclk */
> + idx = EP93XX_CLK_I2S_SCLK - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + pdata.hw = &priv->reg[EP93XX_CLK_I2S_MCLK - EP93XX_CLK_UART1].hw;
> + ret = clk_hw_register_div(clk, "sclk", &pdata,
> + EP93XX_SYSCON_I2SCLKDIV,
> + EP93XX_SYSCON_I2SCLKDIV_SENA,
> + 16, /* EP93XX_I2SCLKDIV_SDIV_SHIFT */
> + 1, /* EP93XX_I2SCLKDIV_SDIV_WIDTH */
> + sclk_divisors,
> + ARRAY_SIZE(sclk_divisors));
> +
> + /* i2s lrclk */
> + idx = EP93XX_CLK_I2S_LRCLK - EP93XX_CLK_UART1;
> + clk = &priv->reg[idx];
> + clk->idx = idx;
> + pdata.hw = &priv->reg[EP93XX_CLK_I2S_SCLK - EP93XX_CLK_UART1].hw;
> + ret = clk_hw_register_div(clk, "lrclk", &pdata,
> + EP93XX_SYSCON_I2SCLKDIV,
> + EP93XX_SYSCON_I2SCLKDIV_SENA,
> + 17, /* EP93XX_I2SCLKDIV_LRDIV32_SHIFT */
> + 2, /* EP93XX_I2SCLKDIV_LRDIV32_WIDTH */
> + lrclk_divisors,
> + ARRAY_SIZE(lrclk_divisors));
> +
> + /* IrDa clk uses same pattern but no init code presents in original clock driver */
> + return devm_of_clk_add_hw_provider(priv->dev, of_clk_ep93xx_get, priv);
> +}
> +
> +static const struct auxiliary_device_id ep93xx_clk_ids[] = {
> + {
> + .name = "soc_ep93xx.clk-ep93xx",
> + },

This can be one line instead of three.

> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(auxiliary, ep93xx_clk_ids);

2024-04-14 09:41:06

by Nikita Shubin

[permalink] [raw]
Subject: Re: [PATCH 2/4] clk: ep93xx: add DT support for Cirrus EP93xx

Hello Stephen!

All notes taken in account, except:

On Thu, 2024-04-11 at 02:32 -0700, Stephen Boyd wrote:
> Quoting Nikita Shubin via B4 Relay (2024-04-08 01:09:54)
> >
> > +       ret = clk_hw_register_div(clk, "ep93xx-adc", &xtali,
>
> Use devm?

This clk-ep93xx internal function and it uses devm:

```
static int clk_hw_register_div(...)
..
return devm_clk_hw_register(priv->dev, &clk->hw);
```