Re: [PATCH v7 07/14] clk: en7523: Add clock driver for Airoha EN7523 SoC

Stephen Boyd
2022-01-06T01:31:30Z

Quoting Felix Fietkau (2021-12-17 03:23:37)
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index c5b3dc97396a..c973ac1a4890 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -192,6 +192,15 @@ config COMMON_CLK_CS2000_CP
> help
> If you say yes here you get support for the CS2000 clock multiplier.
>
> +config COMMON_CLK_EN7523
> + bool "Clock driver for Airoha EN7523 SoC system clocks"
> + depends on OF

What depends on OF?

> + depends on ARCH_AIROHA || COMPILE_TEST
> + default ARCH_AIROHA
> + help
> + This driver provides the fixed clocks and gates present on Airoha
> + ARM silicon.
> +
> 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
> diff --git a/drivers/clk/clk-en7523.c b/drivers/clk/clk-en7523.c
> new file mode 100644
> index 000000000000..828c35da0968
> --- /dev/null
> +++ b/drivers/clk/clk-en7523.c
> @@ -0,0 +1,350 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <linux/regmap.h>

Is this include used? Please remove unused includes.

> +#include <linux/clk-provider.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <dt-bindings/clock/en7523-clk.h>
> +
> +#define REG_PCI_CONTROL 0x88
> +#define REG_PCI_CONTROL_PERSTOUT BIT(29)
> +#define REG_PCI_CONTROL_PERSTOUT1 BIT(26)
> +#define REG_PCI_CONTROL_REFCLK_EN1 BIT(22)
> +#define REG_GSW_CLK_DIV_SEL 0x1b4
> +#define REG_EMI_CLK_DIV_SEL 0x1b8
> +#define REG_BUS_CLK_DIV_SEL 0x1bc
> +#define REG_SPI_CLK_DIV_SEL 0x1c4
> +#define REG_SPI_CLK_FREQ_SEL 0x1c8
> +#define REG_NPU_CLK_DIV_SEL 0x1fc
> +#define REG_CRYPTO_CLKSRC 0x200
> +#define REG_RESET_CONTROL 0x834
> +#define REG_RESET_CONTROL_PCIEHB BIT(29)
> +#define REG_RESET_CONTROL_PCIE1 BIT(27)
> +#define REG_RESET_CONTROL_PCIE2 BIT(26)
> +
> +struct en_clk_desc {
> + int id;
> + const char *name;
> + u32 base_reg;
> + u32 base_bits;
> + u32 base_shift;
> + union {
> + const u32 *base_values;
> + u32 base_value;
> + };
> + int n_base_values;
> +
> + u32 div_reg;
> + u32 div_bits;
> + u32 div_shift;
> + u32 div_val0;
> + u32 div_step;
> +};
> +
> +struct en_clk_gate {
> + void __iomem *base;
> + struct clk_hw hw;
> +};
> +
> +static const u32 gsw_base[] = { 400000000, 500000000 };
> +static const u32 emi_base[] = { 333000000, 400000000 };
> +static const u32 bus_base[] = { 500000000, 540000000 };
> +static const u32 slic_base[] = { 100000000, 3125000 };
> +static const u32 npu_base[] = { 333000000, 400000000, 500000000 };
> +
> +static const struct en_clk_desc en7523_base_clks[] = {
> + {
> + .id = EN7523_CLK_GSW,
> + .name = "gsw",
> +
> + .base_reg = REG_GSW_CLK_DIV_SEL,
> + .base_bits = 1,
> + .base_shift = 8,
> + .base_values = gsw_base,
> + .n_base_values = ARRAY_SIZE(gsw_base),
> +
> + .div_bits = 3,
> + .div_shift = 0,
> + .div_step = 1,
> + }, {
> + .id = EN7523_CLK_EMI,
> + .name = "emi",
> +
> + .base_reg = REG_EMI_CLK_DIV_SEL,
> + .base_bits = 1,
> + .base_shift = 8,
> + .base_values = emi_base,
> + .n_base_values = ARRAY_SIZE(emi_base),
> +
> + .div_bits = 3,
> + .div_shift = 0,
> + .div_step = 1,
> + }, {
> + .id = EN7523_CLK_BUS,
> + .name = "bus",
> +
> + .base_reg = REG_BUS_CLK_DIV_SEL,
> + .base_bits = 1,
> + .base_shift = 8,
> + .base_values = bus_base,
> + .n_base_values = ARRAY_SIZE(bus_base),
> +
> + .div_bits = 3,
> + .div_shift = 0,
> + .div_step = 1,
> + }, {
> + .id = EN7523_CLK_SLIC,
> + .name = "slic",
> +
> + .base_reg = REG_SPI_CLK_FREQ_SEL,
> + .base_bits = 1,
> + .base_shift = 0,
> + .base_values = slic_base,
> + .n_base_values = ARRAY_SIZE(slic_base),
> +
> + .div_reg = REG_SPI_CLK_DIV_SEL,
> + .div_bits = 5,
> + .div_shift = 24,
> + .div_val0 = 20,
> + .div_step = 2,
> + }, {
> + .id = EN7523_CLK_SPI,
> + .name = "spi",
> +
> + .base_reg = REG_SPI_CLK_DIV_SEL,
> +
> + .base_value = 400000000,
> +
> + .div_bits = 5,
> + .div_shift = 8,
> + .div_val0 = 40,
> + .div_step = 2,
> + }, {
> + .id = EN7523_CLK_NPU,
> + .name = "npu",
> +
> + .base_reg = REG_NPU_CLK_DIV_SEL,
> + .base_bits = 2,
> + .base_shift = 8,
> + .base_values = npu_base,
> + .n_base_values = ARRAY_SIZE(npu_base),
> +
> + .div_bits = 3,
> + .div_shift = 0,
> + .div_step = 1,
> + }, {
> + .id = EN7523_CLK_CRYPTO,
> + .name = "crypto",
> +
> + .base_reg = REG_CRYPTO_CLKSRC,
> + .base_bits = 1,
> + .base_shift = 8,
> + .base_values = emi_base,
> + .n_base_values = ARRAY_SIZE(emi_base),
> + }
> +};
> +
> +static const struct of_device_id of_match_clk_en7523[] = {

Please move this down near the driver struct that uses it.

> + { .compatible = "airoha,en7523-scu", },
> + { /* sentinel */ }
> +};
> +
> +static u32 en7523_get_base_rate(void __iomem *base, int i)
> +{
> + const struct en_clk_desc *desc = &en7523_base_clks[i];
> + u32 val;
> +
> + if (!desc->base_bits)
> + return desc->base_value;
> +
> + val = readl(base + desc->base_reg);
> + val >>= desc->base_shift;
> + val &= (1 << desc->base_bits) - 1;
> +
> + if (val >= desc->n_base_values)
> + return 0;
> +
> + return desc->base_values[val];
> +}
> +
> +static u32 en7523_get_div(void __iomem *base, int i)
> +{
> + const struct en_clk_desc *desc = &en7523_base_clks[i];
> + u32 reg, val;
> +
> + if (!desc->div_bits)
> + return 1;
> +
> + reg = desc->div_reg ? desc->div_reg : desc->base_reg;
> + val = readl(base + reg);
> + val >>= desc->div_shift;
> + val &= (1 << desc->div_bits) - 1;
> +
> + if (!val && desc->div_val0)
> + return desc->div_val0;
> +
> + return (val + 1) * desc->div_step;
> +}
> +
> +static int en7523_pci_is_enabled(struct clk_hw *hw)
> +{
> + struct en_clk_gate *cg = container_of(hw, struct en_clk_gate, hw);
> +
> + return !!(readl(cg->base + REG_PCI_CONTROL) & REG_PCI_CONTROL_REFCLK_EN1);
> +}
> +
> +static int en7523_pci_enable(struct clk_hw *hw)
> +{
> + struct en_clk_gate *cg = container_of(hw, struct en_clk_gate, hw);
> + void __iomem *np_base = cg->base;
> + u32 val, mask;
> +
> + /* Need to pull device low before reset */
> + val = readl(np_base + REG_PCI_CONTROL);
> + val &= ~(REG_PCI_CONTROL_PERSTOUT1 | REG_PCI_CONTROL_PERSTOUT);
> + writel(val, np_base + REG_PCI_CONTROL);
> + usleep_range(1000, 2000);

This clk_op is called under a spinlock and thus nothing in here can
sleep. These need to be udelays and mdelays instead, or this needs to be
a prepare clk_op.

> +
> + /* Enable PCIe port 1 */
> + val |= REG_PCI_CONTROL_REFCLK_EN1;
> + writel(val, np_base + REG_PCI_CONTROL);
> + usleep_range(1000, 2000);
> +
> + /* Reset to default */
> + val = readl(np_base + REG_RESET_CONTROL);
> + mask = REG_RESET_CONTROL_PCIE1 | REG_RESET_CONTROL_PCIE2 |
> + REG_RESET_CONTROL_PCIEHB;
> + writel(val & ~mask, np_base + REG_RESET_CONTROL);
> + usleep_range(1000, 2000);
> + writel(val | mask, np_base + REG_RESET_CONTROL);
> + msleep(100);
> + writel(val & ~mask, np_base + REG_RESET_CONTROL);
> + usleep_range(5000, 10000);
> +
> + /* Release device */
> + mask = REG_PCI_CONTROL_PERSTOUT1 | REG_PCI_CONTROL_PERSTOUT;
> + val = readl(np_base + REG_PCI_CONTROL);
> + writel(val & ~mask, np_base + REG_PCI_CONTROL);
> + usleep_range(1000, 2000);
> + writel(val | mask, np_base + REG_PCI_CONTROL);
> + msleep(250);
> +
> + return 0;
> +}
> +
> +static void en7523_pci_disable(struct clk_hw *hw)
> +{
> + struct en_clk_gate *cg = container_of(hw, struct en_clk_gate, hw);
> + void *np_base = cg->base;
> + u32 val;
> +
> + val = readl(np_base + REG_PCI_CONTROL);
> + val &= ~REG_PCI_CONTROL_REFCLK_EN1;
> + writel(val, np_base + REG_PCI_CONTROL);
> +}
> +
> +static struct clk_hw *en7523_register_pcie_clk(struct device *dev,
> + void __iomem *np_base)
> +{
> + static const struct clk_ops pcie_gate_ops = {
> + .is_enabled = en7523_pci_is_enabled,
> + .enable = en7523_pci_enable,
> + .disable = en7523_pci_disable,
> + };
> + struct clk_init_data init = {
> + .name = "pcie",
> + .ops = &pcie_gate_ops,
> + };
> + struct en_clk_gate *cg;
> +
> + cg = devm_kzalloc(dev, sizeof(*cg), GFP_KERNEL);
> + if (!cg)
> + return NULL;
> +
> + cg->base = np_base;
> + cg->hw.init = &init;
> + en7523_pci_disable(&cg->hw);
> +
> + if (clk_hw_register(NULL, &cg->hw))
> + return NULL;
> +
> + return &cg->hw;
> +}
> +
> +static void en7523_register_clocks(struct device *dev, struct clk_hw_onecell_data *clk_data,
> + void __iomem *base, void __iomem *np_base)
> +{
> + struct clk_hw *hw;
> + u32 rate;
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(en7523_base_clks); i++) {
> + const struct en_clk_desc *desc = &en7523_base_clks[i];
> +
> + rate = en7523_get_base_rate(base, i);
> + rate /= en7523_get_div(base, i);
> +
> + hw = clk_hw_register_fixed_rate(NULL, desc->name, NULL, 0, rate);

Please pass 'dev' to this function.

> + if (IS_ERR(hw)) {
> + pr_err("Failed to register clk %s: %ld\n",
> + desc->name, PTR_ERR(hw));
> + continue;
> + }
> +
> + clk_data->hws[desc->id] = hw;
> + }
> +
> + hw = en7523_register_pcie_clk(dev, np_base);
> + clk_data->hws[EN7523_CLK_PCIE] = hw;
> +
> + clk_data->num = EN7523_NUM_CLOCKS;
> +}
> +
> +static int en7523_clk_probe(struct platform_device *pdev)
> +{
> + struct device_node *node = pdev->dev.of_node;
> + struct clk_hw_onecell_data *clk_data;
> + void __iomem *base, *np_base;
> + int r;
> +
> + base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + np_base = devm_platform_ioremap_resource(pdev, 1);
> + if (IS_ERR(base))
> + return PTR_ERR(np_base);
> +
> + clk_data = devm_kzalloc(&pdev->dev,
> + struct_size(clk_data, hws, EN7523_NUM_CLOCKS),
> + GFP_KERNEL);
> + if (!clk_data)
> + return -ENOMEM;
> +
> + en7523_register_clocks(&pdev->dev, clk_data, base, np_base);
> +
> + r = of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
> + if (r)
> + dev_err(&pdev->dev,
> + "could not register clock provider: %s: %d\n",
> + pdev->name, r);
> +
> + return r;
> +}
> +
> +static struct platform_driver clk_en7523_drv = {
> + .probe = en7523_clk_probe,
> + .driver = {
> + .name = "clk-en7523",
> + .of_match_table = of_match_clk_en7523,
> + },
> +};
> +
> +static int clk_en7523_init(void)

Add __init

> +{
> + return platform_driver_register(&clk_en7523_drv);
> +}
> +
> +arch_initcall(clk_en7523_init);