clk: microchip: Add driver for Microchip PolarFire SoC
authorDaire McNamara <daire.mcnamara@microchip.com>
Tue, 22 Feb 2022 12:11:44 +0000 (12:11 +0000)
committerStephen Boyd <sboyd@kernel.org>
Sat, 12 Mar 2022 03:31:52 +0000 (19:31 -0800)
Add support for clock configuration on Microchip PolarFire SoC

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Co-developed-by: Padmarao Begari <padmarao.begari@microchip.com>
Signed-off-by: Padmarao Begari <padmarao.begari@microchip.com>
Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
Co-developed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220222121143.3316880-2-conor.dooley@microchip.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
drivers/clk/Kconfig
drivers/clk/Makefile
drivers/clk/microchip/Kconfig [new file with mode: 0644]
drivers/clk/microchip/Makefile
drivers/clk/microchip/clk-mpfs.c [new file with mode: 0644]

index ad4256d..678a865 100644 (file)
@@ -330,9 +330,6 @@ config COMMON_CLK_PXA
        help
          Support for the Marvell PXA SoC.
 
-config COMMON_CLK_PIC32
-       def_bool COMMON_CLK && MACH_PIC32
-
 config COMMON_CLK_OXNAS
        bool "Clock driver for the OXNAS SoC Family"
        depends on ARCH_OXNAS || COMPILE_TEST
@@ -407,6 +404,7 @@ source "drivers/clk/keystone/Kconfig"
 source "drivers/clk/mediatek/Kconfig"
 source "drivers/clk/meson/Kconfig"
 source "drivers/clk/mstar/Kconfig"
+source "drivers/clk/microchip/Kconfig"
 source "drivers/clk/mvebu/Kconfig"
 source "drivers/clk/pistachio/Kconfig"
 source "drivers/clk/qcom/Kconfig"
index 16e5886..6127192 100644 (file)
@@ -91,7 +91,7 @@ obj-$(CONFIG_ARCH_KEYSTONE)           += keystone/
 obj-$(CONFIG_MACH_LOONGSON32)          += loongson1/
 obj-y                                  += mediatek/
 obj-$(CONFIG_ARCH_MESON)               += meson/
-obj-$(CONFIG_MACH_PIC32)               += microchip/
+obj-y                                  += microchip/
 ifeq ($(CONFIG_COMMON_CLK), y)
 obj-$(CONFIG_ARCH_MMP)                 += mmp/
 endif
diff --git a/drivers/clk/microchip/Kconfig b/drivers/clk/microchip/Kconfig
new file mode 100644 (file)
index 0000000..a5a9987
--- /dev/null
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config COMMON_CLK_PIC32
+       def_bool COMMON_CLK && MACH_PIC32
+
+config MCHP_CLK_MPFS
+       bool "Clk driver for PolarFire SoC"
+       depends on (RISCV && SOC_MICROCHIP_POLARFIRE) || COMPILE_TEST
+       help
+         Supports Clock Configuration for PolarFire SoC
index f34b247..5fa6dcf 100644 (file)
@@ -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_MPFS) += clk-mpfs.o
diff --git a/drivers/clk/microchip/clk-mpfs.c b/drivers/clk/microchip/clk-mpfs.c
new file mode 100644 (file)
index 0000000..aa1561b
--- /dev/null
@@ -0,0 +1,381 @@
+// 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <dt-bindings/clock/microchip,mpfs-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
+
+struct mpfs_clock_data {
+       void __iomem *base;
+       struct clk_hw_onecell_data hw_data;
+};
+
+struct mpfs_cfg_clock {
+       const struct clk_div_table *table;
+       unsigned int id;
+       u8 shift;
+       u8 width;
+};
+
+struct mpfs_cfg_hw_clock {
+       struct mpfs_cfg_clock cfg;
+       void __iomem *sys_base;
+       struct clk_hw hw;
+       struct clk_init_data init;
+};
+
+#define to_mpfs_cfg_clk(_hw) container_of(_hw, struct mpfs_cfg_hw_clock, hw)
+
+struct mpfs_periph_clock {
+       unsigned int id;
+       u8 shift;
+};
+
+struct mpfs_periph_hw_clock {
+       struct mpfs_periph_clock periph;
+       void __iomem *sys_base;
+       struct clk_hw hw;
+};
+
+#define to_mpfs_periph_clk(_hw) container_of(_hw, struct mpfs_periph_hw_clock, hw)
+
+/*
+ * mpfs_clk_lock prevents anything else from writing to the
+ * mpfs clk block while a software locked register is being written.
+ */
+static DEFINE_SPINLOCK(mpfs_clk_lock);
+
+static const struct clk_parent_data mpfs_cfg_parent[] = {
+       { .index = 0 },
+};
+
+static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
+       { 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
+       { 0, 0 }
+};
+
+static const struct clk_div_table mpfs_div_ahb_table[] = {
+       { 1, 2 }, { 2, 4}, { 3, 8 },
+       { 0, 0 }
+};
+
+static unsigned long mpfs_cfg_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+       struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+       void __iomem *base_addr = cfg_hw->sys_base;
+       u32 val;
+
+       val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR) >> cfg->shift;
+       val &= clk_div_mask(cfg->width);
+
+       return prate / (1u << val);
+}
+
+static long mpfs_cfg_clk_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
+{
+       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+       struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+
+       return divider_round_rate(hw, rate, prate, cfg->table, cfg->width, 0);
+}
+
+static int mpfs_cfg_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
+{
+       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+       struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+       void __iomem *base_addr = cfg_hw->sys_base;
+       unsigned long flags;
+       u32 val;
+       int divider_setting;
+
+       divider_setting = divider_get_val(rate, prate, cfg->table, cfg->width, 0);
+
+       if (divider_setting < 0)
+               return divider_setting;
+
+       spin_lock_irqsave(&mpfs_clk_lock, flags);
+
+       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);
+
+       spin_unlock_irqrestore(&mpfs_clk_lock, flags);
+
+       return 0;
+}
+
+static const struct clk_ops mpfs_clk_cfg_ops = {
+       .recalc_rate = mpfs_cfg_clk_recalc_rate,
+       .round_rate = mpfs_cfg_clk_round_rate,
+       .set_rate = mpfs_cfg_clk_set_rate,
+};
+
+#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags) {         \
+       .cfg.id = _id,                                                          \
+       .cfg.shift = _shift,                                                    \
+       .cfg.width = _width,                                                    \
+       .cfg.table = _table,                                                    \
+       .hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_cfg_ops,  \
+                                           _flags),                            \
+}
+
+static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
+       CLK_CFG(CLK_CPU, "clk_cpu", mpfs_cfg_parent, 0, 2, mpfs_div_cpu_axi_table, 0),
+       CLK_CFG(CLK_AXI, "clk_axi", mpfs_cfg_parent, 2, 2, mpfs_div_cpu_axi_table, 0),
+       CLK_CFG(CLK_AHB, "clk_ahb", mpfs_cfg_parent, 4, 2, mpfs_div_ahb_table, 0),
+};
+
+static int mpfs_clk_register_cfg(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hw,
+                                void __iomem *sys_base)
+{
+       cfg_hw->sys_base = sys_base;
+
+       return devm_clk_hw_register(dev, &cfg_hw->hw);
+}
+
+static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
+                                 unsigned int num_clks, struct mpfs_clock_data *data)
+{
+       void __iomem *sys_base = data->base;
+       unsigned int i, id;
+       int ret;
+
+       for (i = 0; i < num_clks; i++) {
+               struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
+
+               ret = mpfs_clk_register_cfg(dev, cfg_hw, sys_base);
+               if (ret)
+                       return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
+                                            cfg_hw->cfg.id);
+
+               id = cfg_hws[i].cfg.id;
+               data->hw_data.hws[id] = &cfg_hw->hw;
+       }
+
+       return 0;
+}
+
+static int mpfs_periph_clk_enable(struct clk_hw *hw)
+{
+       struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+       struct mpfs_periph_clock *periph = &periph_hw->periph;
+       void __iomem *base_addr = periph_hw->sys_base;
+       u32 reg, val;
+       unsigned long flags;
+
+       spin_lock_irqsave(&mpfs_clk_lock, flags);
+
+       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);
+
+       spin_unlock_irqrestore(&mpfs_clk_lock, flags);
+
+       return 0;
+}
+
+static void mpfs_periph_clk_disable(struct clk_hw *hw)
+{
+       struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+       struct mpfs_periph_clock *periph = &periph_hw->periph;
+       void __iomem *base_addr = periph_hw->sys_base;
+       u32 reg, val;
+       unsigned long flags;
+
+       spin_lock_irqsave(&mpfs_clk_lock, flags);
+
+       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);
+
+       spin_unlock_irqrestore(&mpfs_clk_lock, flags);
+}
+
+static int mpfs_periph_clk_is_enabled(struct clk_hw *hw)
+{
+       struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+       struct mpfs_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 const struct clk_ops mpfs_periph_clk_ops = {
+       .enable = mpfs_periph_clk_enable,
+       .disable = mpfs_periph_clk_disable,
+       .is_enabled = mpfs_periph_clk_is_enabled,
+};
+
+#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {                      \
+       .periph.id = _id,                                                       \
+       .periph.shift = _shift,                                                 \
+       .hw.init = CLK_HW_INIT_HW(_name, _parent, &mpfs_periph_clk_ops,         \
+                                 _flags),                                      \
+}
+
+#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT].hw)
+
+/*
+ * Critical clocks:
+ * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
+ *   trap handler
+ * - CLK_MMUART0: reserved by the hss
+ * - CLK_DDRC: provides clock to the ddr subsystem
+ * - CLK_FICx: these provide clocks for sections of the fpga fabric, disabling them would
+ *   cause the fabric to go into reset
+ */
+
+static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
+       CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
+       CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
+       CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
+       CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(AHB), 4, 0),
+       CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
+       CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
+       CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
+       CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
+       CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
+       CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
+       CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
+       CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
+       CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
+       CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
+       CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
+       CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, 0),
+       CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
+       CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
+       CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
+       CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
+       CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AHB), 24, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AHB), 25, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AHB), 26, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AHB), 27, CLK_IS_CRITICAL),
+       CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AHB), 28, 0),
+       CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
+};
+
+static int mpfs_clk_register_periph(struct device *dev, struct mpfs_periph_hw_clock *periph_hw,
+                                   void __iomem *sys_base)
+{
+       periph_hw->sys_base = sys_base;
+
+       return devm_clk_hw_register(dev, &periph_hw->hw);
+}
+
+static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
+                                    int num_clks, struct mpfs_clock_data *data)
+{
+       void __iomem *sys_base = data->base;
+       unsigned int i, id;
+       int ret;
+
+       for (i = 0; i < num_clks; i++) {
+               struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
+
+               ret = mpfs_clk_register_periph(dev, periph_hw, sys_base);
+               if (ret)
+                       return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
+                                            periph_hw->periph.id);
+
+               id = periph_hws[i].periph.id;
+               data->hw_data.hws[id] = &periph_hw->hw;
+       }
+
+       return 0;
+}
+
+static int mpfs_clk_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct mpfs_clock_data *clk_data;
+       unsigned int num_clks;
+       int ret;
+
+       /* CLK_RESERVED is not part of cfg_clks nor periph_clks, so add 1 */
+       num_clks = ARRAY_SIZE(mpfs_cfg_clks) + ARRAY_SIZE(mpfs_periph_clks) + 1;
+
+       clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
+       if (!clk_data)
+               return -ENOMEM;
+
+       clk_data->base = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(clk_data->base))
+               return PTR_ERR(clk_data->base);
+
+       clk_data->hw_data.num = num_clks;
+
+       ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
+       if (ret)
+               return ret;
+
+       ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
+                                       clk_data);
+       if (ret)
+               return ret;
+
+       ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
+       if (ret)
+               return ret;
+
+       return ret;
+}
+
+static const struct of_device_id mpfs_clk_of_match_table[] = {
+       { .compatible = "microchip,mpfs-clkcfg", },
+       {}
+};
+MODULE_DEVICE_TABLE(of, mpfs_clk_match_table);
+
+static struct platform_driver mpfs_clk_driver = {
+       .probe = mpfs_clk_probe,
+       .driver = {
+               .name = "microchip-mpfs-clkcfg",
+               .of_match_table = mpfs_clk_of_match_table,
+       },
+};
+
+static int __init clk_mpfs_init(void)
+{
+       return platform_driver_register(&mpfs_clk_driver);
+}
+core_initcall(clk_mpfs_init);
+
+static void __exit clk_mpfs_exit(void)
+{
+       platform_driver_unregister(&mpfs_clk_driver);
+}
+module_exit(clk_mpfs_exit);
+
+MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
+MODULE_LICENSE("GPL v2");