[PATCH v1 2/2] CLK: microchip: Add driver for Microchip PolarFire SoC

daire.mcnamara
2020-10-15T11:49:42Z

From: Daire McNamara <daire.mcnamara@microchip.com>

Add support for clock configuration on Microchip PolarFire SoC

Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
---
drivers/clk/Kconfig | 5 +
drivers/clk/Makefile | 1 +
drivers/clk/microchip/Makefile | 1 +
drivers/clk/microchip/clk-pfsoc.c | 424 ++++++++++++++++++
.../dt-bindings/clock/microchip,pfsoc-clock.h | 45 ++
5 files changed, 476 insertions(+)
create mode 100644 drivers/clk/microchip/clk-pfsoc.c
create mode 100644 include/dt-bindings/clock/microchip,pfsoc-clock.h

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 4026fac9fac3..5ba96ba3028a 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -359,6 +359,11 @@ config COMMON_CLK_FIXED_MMIO
help
Support for Memory Mapped IO Fixed clocks

+config MCHP_CLK_PFSOC
+ bool "Clk driver for PolarFire SoC"
+ help
+ Supports Clock Configuration for PolarFire SoC
+
source "drivers/clk/actions/Kconfig"
source "drivers/clk/analogbits/Kconfig"
source "drivers/clk/baikal-t1/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index da8fcf147eb1..a3d4ad288053 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_MACH_LOONGSON32) += loongson1/
obj-y += mediatek/
obj-$(CONFIG_ARCH_MESON) += meson/
obj-$(CONFIG_MACH_PIC32) += microchip/
+obj-$(CONFIG_MCHP_CLK_PFSOC) += microchip/
ifeq ($(CONFIG_COMMON_CLK), y)
obj-$(CONFIG_ARCH_MMP) += mmp/
endif
diff --git a/drivers/clk/microchip/Makefile b/drivers/clk/microchip/Makefile
index f34b247e870f..55156dd15596 100644
--- a/drivers/clk/microchip/Makefile
+++ b/drivers/clk/microchip/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_COMMON_CLK_PIC32) += clk-core.o
obj-$(CONFIG_PIC32MZDA) += clk-pic32mzda.o
+obj-$(CONFIG_MCHP_CLK_PFSOC) += clk-pfsoc.o
diff --git a/drivers/clk/microchip/clk-pfsoc.c b/drivers/clk/microchip/clk-pfsoc.c
new file mode 100644
index 000000000000..affd023ef084
--- /dev/null
+++ b/drivers/clk/microchip/clk-pfsoc.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Daire McNamara,<daire.mcnamara@microchip.com>
+ * Copyright (C) 2020 Microchip Technology Inc. All rights reserved.
+ */
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <dt-bindings/clock/microchip,pfsoc-clock.h>
+
+/* address offset of control registers */
+#define REG_CLOCK_CONFIG_CR 0x08u
+#define REG_SUBBLK_CLOCK_CR 0x84u
+#define REG_SUBBLK_RESET_CR 0x88u
+
+/*
+ * pfsoc_clk_lock prevents anything else from writing to the
+ * pfsoc clk block while a software locked register is being written.
+ */
+static DEFINE_SPINLOCK(pfsoc_clk_lock);
+
+static struct clk_parent_data pfsoc_cfg_parent[] = {
+ { .fw_name = "msspllclk", .name = "msspllclk" },
+};
+
+struct pfsoc_clock_data {
+ void __iomem *reg;
+ struct clk_hw_onecell_data hw_data;
+};
+
+static const struct clk_div_table pfsoc_div_cpu_axi_table[] = {
+ { 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
+ { 0, 0 }
+};
+
+static const struct clk_div_table pfsoc_div_ahb_table[] = {
+ { 1, 2 }, { 2, 4}, { 3, 8 },
+ { 0, 0 }
+};
+
+struct pfsoc_cfg_clock {
+ unsigned int id;
+ const char *name;
+ u8 shift;
+ u8 width;
+ const struct clk_div_table *table;
+ unsigned long flags;
+};
+
+struct pfsoc_cfg_hw_clock {
+ struct pfsoc_cfg_clock cfg;
+ void __iomem *sys_base;
+ /* lock is used to prevent multiple writes */
+ spinlock_t *lock;
+ struct clk_hw hw;
+ struct clk_init_data init;
+};
+
+#define to_pfsoc_cfg_clk(_hw) container_of(_hw, struct pfsoc_cfg_hw_clock, hw)
+
+static unsigned long pfsoc_cfg_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+ struct pfsoc_cfg_hw_clock *cfg_hw = to_pfsoc_cfg_clk(hw);
+ struct pfsoc_cfg_clock *cfg = &cfg_hw->cfg;
+ void __iomem *base_addr = cfg_hw->sys_base;
+ unsigned long rate;
+ u32 val;
+
+ val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR) >> cfg->shift;
+ val &= clk_div_mask(cfg->width);
+ rate = prate / (1u << val);
+
+ return rate;
+}
+
+static long pfsoc_cfg_clk_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
+{
+ struct pfsoc_cfg_hw_clock *cfg_hw = to_pfsoc_cfg_clk(hw);
+ struct pfsoc_cfg_clock *cfg = &cfg_hw->cfg;
+
+ return divider_round_rate(hw, rate, prate, cfg->table, cfg->width, cfg->flags);
+}
+
+static int pfsoc_cfg_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
+{
+ struct pfsoc_cfg_hw_clock *cfg_hw = to_pfsoc_cfg_clk(hw);
+ struct pfsoc_cfg_clock *cfg = &cfg_hw->cfg;
+ void __iomem *base_addr = cfg_hw->sys_base;
+ unsigned long flags = 0;
+ u32 divider_setting, val;
+
+ divider_setting = divider_get_val(rate, prate, cfg->table, cfg->width, cfg_hw->cfg.flags);
+
+ if (divider_setting < 0)
+ return divider_setting;
+
+ if (cfg_hw->lock)
+ spin_lock_irqsave(cfg_hw->lock, flags);
+ else
+ __acquire(cfg_hw->lock);
+
+ val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR);
+ val &= ~(clk_div_mask(cfg->width) << cfg_hw->cfg.shift);
+ val |= divider_setting << cfg->shift;
+ writel_relaxed(val, base_addr + REG_CLOCK_CONFIG_CR);
+
+ if (cfg_hw->lock)
+ spin_unlock_irqrestore(cfg_hw->lock, flags);
+ else
+ __release(cfg_hw->lock);
+
+ return 0;
+}
+
+static const struct clk_ops pfsoc_clk_cfg_ops = {
+ .recalc_rate = pfsoc_cfg_clk_recalc_rate,
+ .round_rate = pfsoc_cfg_clk_round_rate,
+ .set_rate = pfsoc_cfg_clk_set_rate,
+};
+
+#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags) { \
+ .cfg.id = _id, \
+ .cfg.name = _name, \
+ .cfg.shift = _shift, \
+ .cfg.width = _width, \
+ .cfg.table = _table, \
+ .hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &pfsoc_clk_cfg_ops, \
+ _flags), \
+ }
+
+static struct pfsoc_cfg_hw_clock pfsoc_cfg_clks[] = {
+ CLK_CFG(CLK_CPU, "clk_cpu", pfsoc_cfg_parent, 0, 2, pfsoc_div_cpu_axi_table, 0),
+ CLK_CFG(CLK_AXI, "clk_axi", pfsoc_cfg_parent, 2, 2, pfsoc_div_cpu_axi_table, 0),
+ CLK_CFG(CLK_AHB, "clk_ahb", pfsoc_cfg_parent, 4, 2, pfsoc_div_ahb_table, 0),
+};
+
+#define CPU_PARENT pfsoc_cfg_clks[0].hw
+#define AXI_PARENT pfsoc_cfg_clks[1].hw
+#define AHB_PARENT pfsoc_cfg_clks[2].hw
+
+static void pfsoc_clk_unregister_cfg(struct device *dev, struct clk_hw *hw)
+{
+ struct pfsoc_cfg_hw_clock *cfg_hw = to_pfsoc_cfg_clk(hw);
+
+ devm_clk_hw_unregister(dev, hw);
+ kfree(cfg_hw);
+}
+
+static struct clk_hw *pfsoc_clk_register_cfg(struct device *dev,
+ struct pfsoc_cfg_hw_clock *cfg_hw,
+ void __iomem *sys_base)
+{
+ struct clk_hw *hw;
+ int err;
+
+ cfg_hw->sys_base = sys_base;
+ cfg_hw->lock = &pfsoc_clk_lock;
+
+ hw = &cfg_hw->hw;
+ err = devm_clk_hw_register(dev, hw);
+ if (err)
+ return ERR_PTR(err);
+
+ return hw;
+}
+
+static int pfsoc_clk_register_cfgs(struct device *dev, struct pfsoc_cfg_hw_clock *cfg_hws,
+ int num_clks, struct pfsoc_clock_data *data)
+{
+ struct clk_hw *hw;
+ void __iomem *sys_base = data->reg;
+ unsigned int i, id;
+
+ for (i = 0; i < num_clks; i++) {
+ struct pfsoc_cfg_hw_clock *cfg_hw = &cfg_hws[i];
+
+ hw = pfsoc_clk_register_cfg(dev, cfg_hw, sys_base);
+ if (IS_ERR(hw)) {
+ pr_err("%s: failed to register clock %s\n", __func__,
+ cfg_hw->cfg.name);
+ goto err_clk;
+ }
+
+ id = cfg_hws[i].cfg.id;
+ data->hw_data.hws[id] = hw;
+ }
+
+ return 0;
+
+err_clk:
+ while (i--)
+ pfsoc_clk_unregister_cfg(dev, data->hw_data.hws[cfg_hws[i].cfg.id]);
+
+ return PTR_ERR(hw);
+}
+
+struct pfsoc_periph_clock {
+ unsigned int id;
+ const char *name;
+ u8 shift;
+ unsigned long flags;
+};
+
+struct pfsoc_periph_hw_clock {
+ struct pfsoc_periph_clock periph;
+ void __iomem *sys_base;
+ /* lock is used to prevent multiple writes */
+ spinlock_t *lock;
+ struct clk_hw hw;
+};
+
+#define to_pfsoc_periph_clk(_hw) container_of(_hw, struct pfsoc_periph_hw_clock, hw)
+
+static int pfsoc_periph_clk_enable(struct clk_hw *hw)
+{
+ struct pfsoc_periph_hw_clock *periph_hw = to_pfsoc_periph_clk(hw);
+ struct pfsoc_periph_clock *periph = &periph_hw->periph;
+ void __iomem *base_addr = periph_hw->sys_base;
+ u32 reg, val;
+
+ reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+ val = reg & ~(1u << periph->shift);
+ writel_relaxed(val, base_addr + REG_SUBBLK_RESET_CR);
+
+ reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+ val = reg | (1u << periph->shift);
+ writel_relaxed(val, base_addr + REG_SUBBLK_CLOCK_CR);
+
+ return 0;
+}
+
+static void pfsoc_periph_clk_disable(struct clk_hw *hw)
+{
+ struct pfsoc_periph_hw_clock *periph_hw = to_pfsoc_periph_clk(hw);
+ struct pfsoc_periph_clock *periph = &periph_hw->periph;
+ void __iomem *base_addr = periph_hw->sys_base;
+ u32 reg, val;
+
+ reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+ val = reg | (1u << periph->shift);
+ writel_relaxed(val, base_addr + REG_SUBBLK_RESET_CR);
+
+ reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+ val = reg & ~(1u << periph->shift);
+ writel_relaxed(val, base_addr + REG_SUBBLK_CLOCK_CR);
+}
+
+static int pfsoc_periph_clk_is_enabled(struct clk_hw *hw)
+{
+ struct pfsoc_periph_hw_clock *periph_hw = to_pfsoc_periph_clk(hw);
+ struct pfsoc_periph_clock *periph = &periph_hw->periph;
+ void __iomem *base_addr = periph_hw->sys_base;
+ u32 reg;
+
+ reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+ if ((reg & (1u << periph->shift)) == 0u) {
+ reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+ if (reg & (1u << periph->shift))
+ return 1;
+ }
+
+ return 0;
+}
+
+static unsigned long pfsoc_periph_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+ return prate;
+}
+
+static const struct clk_ops pfsoc_periph_clk_ops = {
+ .enable = pfsoc_periph_clk_enable,
+ .disable = pfsoc_periph_clk_disable,
+ .is_enabled = pfsoc_periph_clk_is_enabled,
+ .recalc_rate = pfsoc_periph_clk_recalc_rate,
+};
+
+#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) { \
+ .periph.id = _id, \
+ .periph.name = _name, \
+ .periph.shift = _shift, \
+ .hw.init = CLK_HW_INIT_HW(_name, _parent, &pfsoc_periph_clk_ops, \
+ _flags), \
+ }
+
+static struct pfsoc_periph_hw_clock pfsoc_periph_clks[] = {
+ CLK_PERIPH(CLK_ENVM, "clk_periph_envm", &AHB_PARENT, 0, CLK_IS_CRITICAL),
+ CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", &AHB_PARENT, 1, 0),
+ CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", &AHB_PARENT, 2, 0),
+ CLK_PERIPH(CLK_MMC, "clk_periph_mmc", &AHB_PARENT, 3, 0),
+ CLK_PERIPH(CLK_TIMER, "clk_periph_timer", &AHB_PARENT, 4, 0),
+ CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", &AHB_PARENT, 5, 0),
+ CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", &AHB_PARENT, 6, 0),
+ CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", &AHB_PARENT, 7, 0),
+ CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", &AHB_PARENT, 8, 0),
+ CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", &AHB_PARENT, 9, 0),
+ CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", &AHB_PARENT, 10, 0),
+ CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", &AHB_PARENT, 11, 0),
+ CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", &AHB_PARENT, 12, 0),
+ CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", &AHB_PARENT, 13, 0),
+ CLK_PERIPH(CLK_CAN0, "clk_periph_can0", &AHB_PARENT, 14, 0),
+ CLK_PERIPH(CLK_CAN1, "clk_periph_can1", &AHB_PARENT, 15, 0),
+ CLK_PERIPH(CLK_USB, "clk_periph_usb", &AHB_PARENT, 16, 0),
+ CLK_PERIPH(CLK_RTC, "clk_periph_rtc", &AHB_PARENT, 18, 0),
+ CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", &AHB_PARENT, 19, 0),
+ CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", &AHB_PARENT, 20, 0),
+ CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", &AHB_PARENT, 21, 0),
+ CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", &AHB_PARENT, 22, 0),
+ CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", &AHB_PARENT, 23, CLK_IS_CRITICAL),
+ CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", &AHB_PARENT, 24, 0),
+ CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", &AHB_PARENT, 25, 0),
+ CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", &AHB_PARENT, 26, 0),
+ CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", &AHB_PARENT, 27, 0),
+ CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", &AHB_PARENT, 28, 0),
+ CLK_PERIPH(CLK_CFM, "clk_periph_cfm", &AHB_PARENT, 29, 0),
+};
+
+static void pfsoc_clk_unregister_periph(struct device *dev, struct clk_hw *hw)
+{
+ struct pfsoc_periph_hw_clock *periph_hw = to_pfsoc_periph_clk(hw);
+
+ devm_clk_hw_unregister(dev, hw);
+ kfree(periph_hw);
+}
+
+static struct clk_hw *pfsoc_clk_register_periph(struct device *dev,
+ struct pfsoc_periph_hw_clock *periph_hw,
+ void __iomem *sys_base)
+{
+ struct clk_hw *hw;
+ int err;
+
+ periph_hw->sys_base = sys_base;
+ periph_hw->lock = &pfsoc_clk_lock;
+
+ hw = &periph_hw->hw;
+ err = devm_clk_hw_register(dev, hw);
+ if (err)
+ return ERR_PTR(err);
+
+ return hw;
+}
+
+static int pfsoc_clk_register_periphs(struct device *dev, struct pfsoc_periph_hw_clock *periph_hws,
+ int num_clks, struct pfsoc_clock_data *data)
+{
+ struct clk_hw *hw;
+ void __iomem *sys_base = data->reg;
+ unsigned int i, id;
+
+ for (i = 0; i < num_clks; i++) {
+ struct pfsoc_periph_hw_clock *periph_hw = &periph_hws[i];
+
+ hw = pfsoc_clk_register_periph(dev, periph_hw, sys_base);
+ if (IS_ERR(hw)) {
+ pr_err("%s: failed to register clock %s\n", __func__,
+ periph_hw->periph.name);
+ goto err_clk;
+ }
+
+ id = periph_hws[i].periph.id;
+ data->hw_data.hws[id] = hw;
+ }
+
+ return 0;
+
+err_clk:
+ while (i--)
+ pfsoc_clk_unregister_periph(dev, data->hw_data.hws[periph_hws[i].periph.id]);
+
+ return PTR_ERR(hw);
+}
+
+static int pfsoc_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pfsoc_clock_data *clk_data;
+ struct resource *res;
+ int num_clks;
+ int ret;
+
+ num_clks = ARRAY_SIZE(pfsoc_cfg_clks) + ARRAY_SIZE(pfsoc_periph_clks);
+
+ clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
+ if (!clk_data)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ clk_data->reg = devm_ioremap_resource(dev, res);
+
+ clk_data->hw_data.num = num_clks;
+
+ pfsoc_clk_register_cfgs(dev, pfsoc_cfg_clks, ARRAY_SIZE(pfsoc_cfg_clks), clk_data);
+
+ pfsoc_clk_register_periphs(dev, pfsoc_periph_clks, ARRAY_SIZE(pfsoc_periph_clks), clk_data);
+
+ ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
+
+ if (ret == 0)
+ dev_info(dev, "registered PFSOC core clocks\n");
+ else
+ dev_err(dev, "failed to register PFSOC core clocks\n");
+
+ return ret;
+}
+
+static const struct of_device_id pfsoc_of_match[] = {
+ { .compatible = "microchip,pfsoc-clkcfg", },
+ {}
+};
+
+static struct platform_driver pfsoc_clk_driver = {
+ .probe = pfsoc_clk_probe,
+ .driver = {
+ .name = "microchip-pfsoc-clkcfg",
+ .of_match_table = pfsoc_of_match,
+ },
+};
+
+static int __init clk_pfsoc_init(void)
+{
+ return platform_driver_register(&pfsoc_clk_driver);
+}
+core_initcall(clk_pfsoc_init);
diff --git a/include/dt-bindings/clock/microchip,pfsoc-clock.h b/include/dt-bindings/clock/microchip,pfsoc-clock.h
new file mode 100644
index 000000000000..c9d8e4f6b963
--- /dev/null
+++ b/include/dt-bindings/clock/microchip,pfsoc-clock.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Daire McNamara,<daire.mcnamara@microchip.com>
+ * Copyright (C) 2020 Microchip Technology Inc. All rights reserved.
+ */
+
+#ifndef _DT_BINDINGS_CLK_MICROCHIP_PFSOC_H_
+#define _DT_BINDINGS_CLK_MICROCHIP_PFSOC_H_
+
+#define CLK_CPU 0
+#define CLK_AXI 1
+#define CLK_AHB 2
+
+#define CLK_ENVM 0
+#define CLK_MAC0 1
+#define CLK_MAC1 2
+#define CLK_MMC 3
+#define CLK_TIMER 4
+#define CLK_MMUART0 5
+#define CLK_MMUART1 6
+#define CLK_MMUART2 7
+#define CLK_MMUART3 8
+#define CLK_MMUART4 9
+#define CLK_SPI0 10
+#define CLK_SPI1 11
+#define CLK_I2C0 12
+#define CLK_I2C1 13
+#define CLK_CAN0 14
+#define CLK_CAN1 15
+#define CLK_USB 16
+#define CLK_RESERVED 17
+#define CLK_RTC 18
+#define CLK_QSPI 19
+#define CLK_GPIO0 20
+#define CLK_GPIO1 21
+#define CLK_GPIO2 22
+#define CLK_DDRC 23
+#define CLK_FIC0 24
+#define CLK_FIC1 25
+#define CLK_FIC2 26
+#define CLK_FIC3 27
+#define CLK_ATHENA 28
+#define CLK_CFM 29
+
+#endif /* _DT_BINDINGS_CLK_MICROCHIP_PFSOC_H_ */
--
2.25.1