lkml.org 
[lkml]   [2023]   [Jun]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 05/43] clk: ep93xx: add DT support for Cirrus EP93xx
Date
This is a rewrite of EP93xx timer driver in
arch/arm/mach-ep93xx/clock.c trying to do everything
the device tree way:

- convert to syscon driver
- provide clock acces via of

Co-developed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
---

Notes:
v0 -> v1:

Stephen Boyd:
- dropped clkdev
- Kconfig sorted
- make lock name uniq
- make divisors const
- u64 rate and drop cast for calc_pll_rate
- use parent_data
- locking all the time
- reworked parents in muxes
- using clk_hw_register everywhere
- inlined defines

rfc -> v0:

Linus Walleij:
- renamed all __underscore

Alexander Sverdlin:
- "Logick" -> "Logic"

Changes by Alexander Sverdlin:
- remove pr_info
- DIV_ROUND_UP_ULL -> DIV_ROUND_CLOSEST
- fix zeroing bitfield in ep93xx_div_set_rate
- add sanity check for EP93XX_SYSCON_CHIPID_ID
- use bit index for DMA clock's
- ep93xx_clk_register_gate() takes bit index, not mask
- remove redundant define
- use DIV_ROUND_CLOSEST() everywhere to achieve frequencies closer to those
requested
- Add the forgotten configuration from the deleted
arch/arm/mach-ep93xx/core.c

drivers/clk/Kconfig | 8 +
drivers/clk/Makefile | 1 +
drivers/clk/clk-ep93xx.c | 850 +++++++++++++++++++++++++++++++++++++++
3 files changed, 859 insertions(+)
create mode 100644 drivers/clk/clk-ep93xx.c

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 1eef05bb1f99..acd28167b46c 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 e3ca0d058a25..deec25ffd004 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -29,6 +29,7 @@ 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..e83571f83b5a
--- /dev/null
+++ b/drivers/clk/clk-ep93xx.c
@@ -0,0 +1,850 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Clock control for Cirrus EP93xx chips.
+ * Copyright (C) 2021 Nikita Shubin <nikita.shubin@maquefel.me>
+ *
+ * Based on a rewrite of arch/arm/mach-ep93xx/clock.c:
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ */
+#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/soc/cirrus/ep93xx.h>
+#include <dt-bindings/clock/cirrus,ep93xx-clock.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_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_I2SCLKDIV_SDIV (1 << 16)
+#define EP93XX_I2SCLKDIV_LRDIV32 (0 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV64 (1 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV128 (2 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV_MASK (3 << 17)
+#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 DEFINE_SPINLOCK(ep93xx_clk_lock);
+static struct regmap *ep93xx_map;
+#define ep93xx_regmap_read(reg, val) regmap_read(ep93xx_map, reg, val)
+#define ep93xx_regmap_write(reg, val) regmap_write(ep93xx_map, reg, val)
+
+/* Keeps track of all clocks */
+static struct clk_hw_onecell_data *ep93xx_clk_data;
+
+static const char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 };
+static const char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 };
+static const char pclk_divisors[] = { 1, 2, 4, 8 };
+
+static const char adc_divisors[] = { 16, 4 };
+static const char sclk_divisors[] = { 2, 4 };
+static const char lrclk_divisors[] = { 32, 64, 128 };
+
+#define EP_PARENT(NAME) { .name = NAME, .fw_name = NAME }
+
+static const struct clk_parent_data ep93xx_clk_parents[] = {
+ EP_PARENT("xtali"),
+ EP_PARENT("pll1"),
+ EP_PARENT("pll2")
+};
+
+/*
+ * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS
+ */
+static unsigned long calc_pll_rate(u64 rate, u32 config_word)
+{
+ int i;
+
+ rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */
+ rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */
+ do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */
+ for (i = 0; i < ((config_word >> 16) & 3); i++) /* PS */
+ rate >>= 1;
+
+ return rate;
+}
+
+struct clk_psc {
+ struct clk_hw hw;
+ unsigned int reg;
+ u8 bit_idx;
+ u32 mask;
+ u8 shift;
+ u8 width;
+ const char *div;
+ u8 num_div;
+ spinlock_t *lock;
+ bool nolock;
+};
+
+#define to_clk_psc(_hw) container_of(_hw, struct clk_psc, hw)
+
+static int ep93xx_clk_is_enabled(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ u32 val;
+
+ ep93xx_regmap_read(psc->reg, &val);
+
+ return (val & BIT(psc->bit_idx)) ? 1 : 0;
+}
+
+static int ep93xx_clk_enable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ unsigned long flags = 0;
+ u32 val;
+
+ spin_lock_irqsave(psc->lock, flags);
+
+ ep93xx_regmap_read(psc->reg, &val);
+ val |= BIT(psc->bit_idx);
+
+ if (psc->nolock)
+ ep93xx_regmap_write(psc->reg, val);
+ else
+ ep93xx_syscon_swlocked_write(val, psc->reg);
+
+ spin_unlock_irqrestore(psc->lock, flags);
+
+ return 0;
+}
+
+static void ep93xx_clk_disable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ unsigned long flags = 0;
+ u32 val;
+
+ spin_lock_irqsave(psc->lock, flags);
+
+ ep93xx_regmap_read(psc->reg, &val);
+ val &= ~BIT(psc->bit_idx);
+
+ if (psc->nolock)
+ ep93xx_regmap_write(psc->reg, val);
+ else
+ ep93xx_syscon_swlocked_write(val, psc->reg);
+
+ spin_unlock_irqrestore(psc->lock, flags);
+}
+
+static const struct clk_ops clk_ep93xx_gate_ops = {
+ .enable = ep93xx_clk_enable,
+ .disable = ep93xx_clk_disable,
+ .is_enabled = ep93xx_clk_is_enabled,
+};
+
+static struct clk_hw *ep93xx_clk_register_gate(const char *name,
+ const char *parent_name,
+ unsigned long flags,
+ unsigned int reg,
+ u8 bit_idx,
+ bool nolock)
+{
+ struct clk_parent_data parent_data = { };
+ struct clk_init_data init = { };
+ struct clk_psc *psc;
+ int ret;
+
+ psc = kzalloc(sizeof(*psc), GFP_KERNEL);
+ if (!psc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_ep93xx_gate_ops;
+ init.flags = flags;
+
+ parent_data.fw_name = parent_name;
+ parent_data.name = parent_name;
+ init.parent_data = &parent_data;
+ init.num_parents = 1;
+
+ psc->reg = reg;
+ psc->bit_idx = bit_idx;
+ psc->hw.init = &init;
+ psc->lock = &ep93xx_clk_lock;
+ psc->nolock = nolock;
+
+ ret = clk_hw_register(NULL, &psc->hw);
+ if (ret) {
+ kfree(psc);
+ return ERR_PTR(ret);
+ }
+
+ return &psc->hw;
+}
+
+static u8 ep93xx_mux_get_parent(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ u32 val;
+
+ ep93xx_regmap_read(psc->reg, &val);
+ if (!(val & EP93XX_SYSCON_CLKDIV_ESEL))
+ return 0;
+
+ if (!(val & EP93XX_SYSCON_CLKDIV_PSEL))
+ return 1;
+
+ return 2;
+}
+
+static int ep93xx_mux_set_parent_lock(struct clk_hw *hw, u8 index)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ unsigned long flags = 0;
+ u32 val;
+
+ if (index >= ARRAY_SIZE(ep93xx_clk_parents))
+ return -EINVAL;
+
+ if (psc->lock)
+ spin_lock_irqsave(psc->lock, flags);
+
+ ep93xx_regmap_read(psc->reg, &val);
+ val &= ~(EP93XX_SYSCON_CLKDIV_ESEL | EP93XX_SYSCON_CLKDIV_PSEL);
+
+ if (index != 0) {
+ val |= EP93XX_SYSCON_CLKDIV_ESEL;
+ val |= (index - 1) ? EP93XX_SYSCON_CLKDIV_PSEL : 0;
+ }
+
+ ep93xx_syscon_swlocked_write(val, psc->reg);
+
+ if (psc->lock)
+ spin_unlock_irqrestore(psc->lock, flags);
+
+ return 0;
+}
+
+static bool is_best(unsigned long rate, unsigned long now,
+ unsigned long best)
+{
+ return abs(rate - now) < abs(rate - best);
+}
+
+static int ep93xx_mux_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ unsigned long rate = req->rate;
+ struct clk_hw *parent_best = NULL;
+ unsigned long parent_rate;
+ unsigned long best_rate = 0, actual_rate, mclk_rate;
+ unsigned long parent_rate_best;
+ int div, pdiv;
+ 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 (div < 1 || div > 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 clk_psc *psc = to_clk_psc(hw);
+ unsigned long rate = 0;
+ u32 val;
+ int pdiv, div;
+
+ ep93xx_regmap_read(psc->reg, &val);
+ pdiv = ((val >> EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) & 0x03);
+ div = val & 0x7f;
+ if (div > 0)
+ rate = DIV_ROUND_CLOSEST(parent_rate * 2, (pdiv + 3) * div);
+
+ return rate;
+}
+
+static int ep93xx_ddiv_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ int pdiv, div, npdiv, ndiv;
+ unsigned long actual_rate, mclk_rate, rate_err = -1;
+ int found = 0;
+ u32 val;
+
+ ep93xx_regmap_read(psc->reg, &val);
+ mclk_rate = parent_rate * 2;
+
+ for (pdiv = 4; pdiv <= 6; pdiv++) {
+ div = DIV_ROUND_CLOSEST(mclk_rate, rate * pdiv);
+ if (div < 1 || div > 127)
+ continue;
+
+ actual_rate = DIV_ROUND_CLOSEST(mclk_rate, pdiv * div);
+
+ if (!found || abs(actual_rate - rate) < rate_err) {
+ npdiv = pdiv - 3;
+ ndiv = div;
+ rate_err = abs(actual_rate - rate);
+ found = 1;
+ }
+ }
+
+ if (!found)
+ return -EINVAL;
+
+ /* Clear old dividers */
+ val &= ~0x37f;
+
+ /* Set the new pdiv and div bits for the new clock rate */
+ val |= (npdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | ndiv;
+
+ ep93xx_syscon_swlocked_write(val, psc->reg);
+
+ 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 struct clk_hw *clk_hw_register_ddiv(const char *name,
+ unsigned int reg,
+ u8 bit_idx)
+{
+ struct clk_init_data init = { };
+ struct clk_psc *psc;
+ int ret;
+
+ psc = kzalloc(sizeof(*psc), GFP_KERNEL);
+ if (!psc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_ddiv_ops;
+ init.flags = 0;
+ init.parent_data = ep93xx_clk_parents;
+ init.num_parents = ARRAY_SIZE(ep93xx_clk_parents);
+
+ psc->reg = reg;
+ psc->bit_idx = bit_idx;
+ psc->lock = &ep93xx_clk_lock;
+ psc->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &psc->hw);
+ if (ret) {
+ kfree(psc);
+ return ERR_PTR(ret);
+ }
+
+ return &psc->hw;
+}
+
+static unsigned long ep93xx_div_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ u32 val;
+ u8 index;
+
+ ep93xx_regmap_read(psc->reg, &val);
+ index = (val & psc->mask) >> psc->shift;
+ if (index > psc->num_div)
+ return 0;
+
+ return DIV_ROUND_CLOSEST(parent_rate, psc->div[index]);
+}
+
+static long ep93xx_div_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ unsigned long best = 0, now;
+ bool assigned = false;
+ int i;
+
+ for (i = 0; i < psc->num_div; i++) {
+ if ((rate * psc->div[i]) == *parent_rate)
+ return rate;
+
+ now = DIV_ROUND_CLOSEST(*parent_rate, psc->div[i]);
+
+ if (!assigned || is_best(rate, now, best))
+ best = now;
+ assigned = true;
+ }
+
+ return best;
+}
+
+static int ep93xx_div_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ u32 val;
+ int i;
+
+ ep93xx_regmap_read(psc->reg, &val);
+ val &= ~psc->mask;
+ for (i = 0; i < psc->num_div; i++)
+ if (rate == DIV_ROUND_CLOSEST(parent_rate, psc->div[i])) {
+ val |= i << psc->shift;
+ break;
+ }
+
+ if (i == psc->num_div)
+ return -EINVAL;
+
+ ep93xx_syscon_swlocked_write(val, psc->reg);
+
+ 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 struct clk_hw *clk_hw_register_div(const char *name,
+ const char *parent_name,
+ unsigned int reg,
+ u8 enable_bit,
+ u8 shift,
+ u8 width,
+ const char *clk_divisors,
+ u8 num_div)
+{
+ struct clk_parent_data parent_data = { };
+ struct clk_init_data init = { };
+ struct clk_psc *psc;
+ int ret;
+
+ psc = kzalloc(sizeof(*psc), GFP_KERNEL);
+ if (!psc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &ep93xx_div_ops;
+ init.flags = 0;
+ parent_data.fw_name = parent_name;
+ parent_data.name = parent_name;
+ init.parent_data = &parent_data;
+ init.num_parents = 1;
+
+ psc->reg = reg;
+ psc->bit_idx = enable_bit;
+ psc->mask = GENMASK(shift + width - 1, shift);
+ psc->shift = shift;
+ psc->div = clk_divisors;
+ psc->num_div = num_div;
+ psc->lock = &ep93xx_clk_lock;
+ psc->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &psc->hw);
+ if (ret) {
+ kfree(psc);
+ return ERR_PTR(ret);
+ }
+
+ return &psc->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 void ep93xx_uart_clock_init(void)
+{
+ unsigned int i;
+ struct clk_hw *hw;
+ u32 val;
+ unsigned int clk_uart_div;
+
+ ep93xx_regmap_read(EP93XX_SYSCON_PWRCNT, &val);
+ if (val & EP93XX_SYSCON_PWRCNT_UARTBAUD)
+ clk_uart_div = 1;
+ else
+ clk_uart_div = 2;
+
+ hw = clk_hw_register_fixed_factor(NULL, "uart", "xtali", 0, 1, clk_uart_div);
+ ep93xx_clk_data->hws[EP93XX_CLK_UART] = hw;
+
+ /* parenting uart gate clocks to uart clock */
+ for (i = 0; i < ARRAY_SIZE(ep93xx_uarts); i++) {
+ hw = ep93xx_clk_register_gate(ep93xx_uarts[i].name,
+ "uart",
+ CLK_SET_RATE_PARENT,
+ EP93XX_SYSCON_DEVCFG,
+ ep93xx_uarts[i].bit,
+ false);
+
+ ep93xx_clk_data->hws[ep93xx_uarts[i].idx] = hw;
+ }
+}
+
+static const struct ep93xx_gate ep93xx_dmas[] = {
+ { 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" },
+ { EP93XX_CLK_M2M0, EP93XX_SYSCON_PWRCNT_DMA_M2M0, "m2m0" },
+ { EP93XX_CLK_M2M1, EP93XX_SYSCON_PWRCNT_DMA_M2M1, "m2m1" },
+};
+
+static void ep93xx_dma_clock_init(void)
+{
+ int i;
+ struct clk_hw *hw;
+
+ for (i = 0; i < ARRAY_SIZE(ep93xx_dmas); i++) {
+ hw = ep93xx_clk_register_gate(ep93xx_dmas[i].name,
+ "hclk", 0,
+ EP93XX_SYSCON_PWRCNT,
+ ep93xx_dmas[i].bit,
+ true);
+
+ ep93xx_clk_data->hws[ep93xx_dmas[i].idx] = hw;
+ }
+}
+
+static int ep93xx_clk_probe(struct platform_device *pdev)
+{
+ unsigned int clk_usb_div;
+ unsigned long clk_spi_div;
+ struct clk_hw *hw;
+ u32 value;
+
+ ep93xx_regmap_read(EP93XX_SYSCON_CLKSET2, &value);
+ clk_usb_div = (((value >> 28) & 0xf) + 1);
+ hw = clk_hw_register_fixed_factor(NULL, "usb_clk", "pll2", 0, 1, clk_usb_div);
+ hw = ep93xx_clk_register_gate("ohci-platform",
+ "usb_clk", 0,
+ EP93XX_SYSCON_PWRCNT,
+ EP93XX_SYSCON_PWRCNT_USH_EN,
+ true);
+ ep93xx_clk_data->hws[EP93XX_CLK_USB] = hw;
+
+ /*
+ * EP93xx SSP clock rate was doubled in version E2. For more information
+ * see:
+ * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
+ */
+ clk_spi_div = 1;
+ if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2)
+ clk_spi_div = 2;
+ hw = clk_hw_register_fixed_factor(NULL, "ep93xx-spi.0", "xtali", 0, 1, clk_spi_div);
+ ep93xx_clk_data->hws[EP93XX_CLK_SPI] = hw;
+
+ /* pwm clock */
+ hw = clk_hw_register_fixed_factor(NULL, "pwm_clk", "xtali", 0, 1, 1);
+ ep93xx_clk_data->hws[EP93XX_CLK_PWM] = hw;
+
+ ep93xx_uart_clock_init();
+
+ /* touchscreen/adc clock */
+ hw = clk_hw_register_div("ep93xx-adc",
+ "xtali",
+ EP93XX_SYSCON_KEYTCHCLKDIV,
+ EP93XX_SYSCON_KEYTCHCLKDIV_TSEN,
+ EP93XX_SYSCON_KEYTCHCLKDIV_ADIV,
+ 1,
+ adc_divisors,
+ ARRAY_SIZE(adc_divisors));
+
+ ep93xx_clk_data->hws[EP93XX_CLK_ADC] = hw;
+
+ /* keypad clock */
+ hw = clk_hw_register_div("ep93xx-keypad",
+ "xtali",
+ EP93XX_SYSCON_KEYTCHCLKDIV,
+ EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
+ EP93XX_SYSCON_KEYTCHCLKDIV_KDIV,
+ 1,
+ adc_divisors,
+ ARRAY_SIZE(adc_divisors));
+
+ ep93xx_clk_data->hws[EP93XX_CLK_KEYPAD] = hw;
+
+ /*
+ * On reset PDIV and VDIV is set to zero, while PDIV zero
+ * means clock disable, VDIV shouldn't be zero.
+ * So i set both dividers to minimum.
+ */
+ /* ENA - Enable CLK divider. */
+ /* PDIV - 00 - Disable clock */
+ /* VDIV - at least 2 */
+ /* Check and enable video clk registers */
+ ep93xx_regmap_read(EP93XX_SYSCON_VIDCLKDIV, &value);
+ value |= (1 << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | 2;
+ ep93xx_syscon_swlocked_write(value, EP93XX_SYSCON_VIDCLKDIV);
+
+ /* check and enable i2s clk registers */
+ ep93xx_regmap_read(EP93XX_SYSCON_I2SCLKDIV, &value);
+ value |= (1 << 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_syscon_swlocked_write(value, EP93XX_SYSCON_I2SCLKDIV);
+
+ /* video clk */
+ hw = clk_hw_register_ddiv("ep93xx-fb",
+ EP93XX_SYSCON_VIDCLKDIV,
+ EP93XX_SYSCON_CLKDIV_ENABLE);
+
+ ep93xx_clk_data->hws[EP93XX_CLK_VIDEO] = hw;
+
+ /* i2s clk */
+ hw = clk_hw_register_ddiv("mclk",
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_CLKDIV_ENABLE);
+
+ ep93xx_clk_data->hws[EP93XX_CLK_I2S_MCLK] = hw;
+
+ /* i2s sclk */
+ hw = clk_hw_register_div("sclk",
+ "mclk",
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_I2SCLKDIV_SENA,
+ 16, /* EP93XX_I2SCLKDIV_SDIV_SHIFT */
+ 1, /* EP93XX_I2SCLKDIV_SDIV_WIDTH */
+ sclk_divisors,
+ ARRAY_SIZE(sclk_divisors));
+
+ ep93xx_clk_data->hws[EP93XX_CLK_I2S_SCLK] = hw;
+
+ /* i2s lrclk */
+ hw = clk_hw_register_div("lrclk",
+ "sclk",
+ EP93XX_SYSCON_I2SCLKDIV,
+ EP93XX_SYSCON_I2SCLKDIV_SENA,
+ 17, /* EP93XX_I2SCLKDIV_LRDIV32_SHIFT */
+ 2, /* EP93XX_I2SCLKDIV_LRDIV32_WIDTH */
+ lrclk_divisors,
+ ARRAY_SIZE(lrclk_divisors));
+
+ ep93xx_clk_data->hws[EP93XX_CLK_I2S_LRCLK] = hw;
+
+ /* IrDa clk uses same pattern but no init code presents in original clock driver */
+ return 0;
+}
+
+static const struct of_device_id ep93xx_clk_dt_ids[] = {
+ { .compatible = "cirrus,ep9301-clk", },
+ { /* sentinel */ }
+};
+
+static struct platform_driver ep93xx_clk_driver = {
+ .probe = ep93xx_clk_probe,
+ .driver = {
+ .name = "ep93xx-clk",
+ .of_match_table = ep93xx_clk_dt_ids,
+ .suppress_bind_attrs = true,
+ },
+};
+builtin_platform_driver(ep93xx_clk_driver);
+
+static void __init ep93xx_clock_init(struct device_node *np)
+{
+ int i;
+ int ret;
+ u32 value;
+ struct clk_hw *hw;
+ struct device_node *parent;
+ unsigned long clk_pll1_rate;
+ unsigned long clk_pll2_rate;
+ unsigned int clk_f_div;
+ unsigned int clk_h_div;
+ unsigned int clk_p_div;
+
+ ep93xx_clk_data = kzalloc(struct_size(ep93xx_clk_data, hws,
+ EP93XX_NUM_CLKS),
+ GFP_KERNEL);
+
+ if (!ep93xx_clk_data)
+ return;
+
+ /*
+ * This way all clock fetched before the platform device probes,
+ * except those we assign here for early use, will be deferred.
+ */
+ for (i = 0; i < EP93XX_NUM_CLKS; i++)
+ ep93xx_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
+
+ parent = of_get_parent(np);
+ if (!parent) {
+ pr_err("no syscon parent for clk node\n");
+ return;
+ }
+
+ ep93xx_map = syscon_node_to_regmap(parent);
+ of_node_put(parent);
+ if (IS_ERR(ep93xx_map)) {
+ pr_err("no syscon regmap\n");
+ return;
+ }
+
+ /*
+ * We check that the regmap works on this very first access,
+ * but as this is an MMIO-backed regmap, subsequent regmap
+ * access is not going to fail and we skip error checks from
+ * this point.
+ */
+ ret = ep93xx_regmap_read(EP93XX_SYSCON_CHIPID, &value);
+ if (ret || (value & 0xffff) != EP93XX_SYSCON_CHIPID_ID) {
+ pr_err("failed to read global status register\n");
+ return;
+ }
+
+ /* Determine the bootloader configured pll1 rate */
+ ep93xx_regmap_read(EP93XX_SYSCON_CLKSET1, &value);
+ if (!(value & EP93XX_SYSCON_CLKSET1_NBYP1))
+ clk_pll1_rate = EP93XX_EXT_CLK_RATE;
+ else
+ clk_pll1_rate = calc_pll_rate(EP93XX_EXT_CLK_RATE, value);
+
+ hw = clk_hw_register_fixed_rate(NULL, "pll1", "xtali", 0, clk_pll1_rate);
+ ep93xx_clk_data->hws[EP93XX_CLK_PLL1] = hw;
+
+ /* Initialize the pll1 derived clocks */
+ clk_f_div = fclk_divisors[(value >> 25) & 0x7];
+ clk_h_div = hclk_divisors[(value >> 20) & 0x7];
+ clk_p_div = pclk_divisors[(value >> 18) & 0x3];
+
+ hw = clk_hw_register_fixed_factor(NULL, "fclk", "pll1", 0, 1, clk_f_div);
+ ep93xx_clk_data->hws[EP93XX_CLK_FCLK] = hw;
+ hw = clk_hw_register_fixed_factor(NULL, "hclk", "pll1", 0, 1, clk_h_div);
+ ep93xx_clk_data->hws[EP93XX_CLK_HCLK] = hw;
+ hw = clk_hw_register_fixed_factor(NULL, "pclk", "hclk", 0, 1, clk_p_div);
+ ep93xx_clk_data->hws[EP93XX_CLK_PCLK] = hw;
+
+ /* Dma probing uses subsys_initcall, so we require to init them early */
+ ep93xx_dma_clock_init();
+
+ /* Determine the bootloader configured pll2 rate */
+ ep93xx_regmap_read(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 = clk_hw_register_fixed_rate(NULL, "pll2", "xtali", 0, clk_pll2_rate);
+ ep93xx_clk_data->hws[EP93XX_CLK_PLL2] = hw;
+
+ ep93xx_clk_data->num = EP93XX_NUM_CLKS;
+ of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ep93xx_clk_data);
+}
+
+CLK_OF_DECLARE_DRIVER(ep93xx, "cirrus,ep9301-clk", ep93xx_clock_init);
--
2.37.4
\
 
 \ /
  Last update: 2023-06-01 07:38    [W:1.243 / U:0.684 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site