diff options
Diffstat (limited to 'drivers/soc/kendryte/k210-sysctl.c')
| -rw-r--r-- | drivers/soc/kendryte/k210-sysctl.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/drivers/soc/kendryte/k210-sysctl.c b/drivers/soc/kendryte/k210-sysctl.c new file mode 100644 index 000000000000..4608fbca20e1 --- /dev/null +++ b/drivers/soc/kendryte/k210-sysctl.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2019 Christoph Hellwig. + * Copyright (c) 2019 Western Digital Corporation or its affiliates. + */ +#include <linux/types.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/bitfield.h> +#include <asm/soc.h> + +#define K210_SYSCTL_CLK0_FREQ 26000000UL + +/* Registers base address */ +#define K210_SYSCTL_SYSCTL_BASE_ADDR 0x50440000ULL + +/* Registers */ +#define K210_SYSCTL_PLL0 0x08 +#define K210_SYSCTL_PLL1 0x0c +/* clkr: 4bits, clkf1: 6bits, clkod: 4bits, bwadj: 4bits */ +#define PLL_RESET (1 << 20) +#define PLL_PWR (1 << 21) +#define PLL_INTFB (1 << 22) +#define PLL_BYPASS (1 << 23) +#define PLL_TEST (1 << 24) +#define PLL_OUT_EN (1 << 25) +#define PLL_TEST_EN (1 << 26) +#define K210_SYSCTL_PLL_LOCK 0x18 +#define PLL0_LOCK1 (1 << 0) +#define PLL0_LOCK2 (1 << 1) +#define PLL0_SLIP_CLEAR (1 << 2) +#define PLL0_TEST_CLK_OUT (1 << 3) +#define PLL1_LOCK1 (1 << 8) +#define PLL1_LOCK2 (1 << 9) +#define PLL1_SLIP_CLEAR (1 << 10) +#define PLL1_TEST_CLK_OUT (1 << 11) +#define PLL2_LOCK1 (1 << 16) +#define PLL2_LOCK2 (1 << 16) +#define PLL2_SLIP_CLEAR (1 << 18) +#define PLL2_TEST_CLK_OUT (1 << 19) +#define K210_SYSCTL_CLKSEL0 0x20 +#define CLKSEL_ACLK (1 << 0) +#define K210_SYSCTL_CLKEN_CENT 0x28 +#define CLKEN_CPU (1 << 0) +#define CLKEN_SRAM0 (1 << 1) +#define CLKEN_SRAM1 (1 << 2) +#define CLKEN_APB0 (1 << 3) +#define CLKEN_APB1 (1 << 4) +#define CLKEN_APB2 (1 << 5) +#define K210_SYSCTL_CLKEN_PERI 0x2c +#define CLKEN_ROM (1 << 0) +#define CLKEN_DMA (1 << 1) +#define CLKEN_AI (1 << 2) +#define CLKEN_DVP (1 << 3) +#define CLKEN_FFT (1 << 4) +#define CLKEN_GPIO (1 << 5) +#define CLKEN_SPI0 (1 << 6) +#define CLKEN_SPI1 (1 << 7) +#define CLKEN_SPI2 (1 << 8) +#define CLKEN_SPI3 (1 << 9) +#define CLKEN_I2S0 (1 << 10) +#define CLKEN_I2S1 (1 << 11) +#define CLKEN_I2S2 (1 << 12) +#define CLKEN_I2C0 (1 << 13) +#define CLKEN_I2C1 (1 << 14) +#define CLKEN_I2C2 (1 << 15) +#define CLKEN_UART1 (1 << 16) +#define CLKEN_UART2 (1 << 17) +#define CLKEN_UART3 (1 << 18) +#define CLKEN_AES (1 << 19) +#define CLKEN_FPIO (1 << 20) +#define CLKEN_TIMER0 (1 << 21) +#define CLKEN_TIMER1 (1 << 22) +#define CLKEN_TIMER2 (1 << 23) +#define CLKEN_WDT0 (1 << 24) +#define CLKEN_WDT1 (1 << 25) +#define CLKEN_SHA (1 << 26) +#define CLKEN_OTP (1 << 27) +#define CLKEN_RTC (1 << 29) + +struct k210_sysctl { + void __iomem *regs; + struct clk_hw hw; +}; + +static void k210_set_bits(u32 val, void __iomem *reg) +{ + writel(readl(reg) | val, reg); +} + +static void k210_clear_bits(u32 val, void __iomem *reg) +{ + writel(readl(reg) & ~val, reg); +} + +static void k210_pll1_enable(void __iomem *regs) +{ + u32 val; + + val = readl(regs + K210_SYSCTL_PLL1); + val &= ~GENMASK(19, 0); /* clkr1 = 0 */ + val |= FIELD_PREP(GENMASK(9, 4), 0x3B); /* clkf1 = 59 */ + val |= FIELD_PREP(GENMASK(13, 10), 0x3); /* clkod1 = 3 */ + val |= FIELD_PREP(GENMASK(19, 14), 0x3B); /* bwadj1 = 59 */ + writel(val, regs + K210_SYSCTL_PLL1); + + k210_clear_bits(PLL_BYPASS, regs + K210_SYSCTL_PLL1); + k210_set_bits(PLL_PWR, regs + K210_SYSCTL_PLL1); + + /* + * Reset the pll. The magic NOPs come from the Kendryte reference SDK. + */ + k210_clear_bits(PLL_RESET, regs + K210_SYSCTL_PLL1); + k210_set_bits(PLL_RESET, regs + K210_SYSCTL_PLL1); + nop(); + nop(); + k210_clear_bits(PLL_RESET, regs + K210_SYSCTL_PLL1); + + for (;;) { + val = readl(regs + K210_SYSCTL_PLL_LOCK); + if (val & PLL1_LOCK2) + break; + writel(val | PLL1_SLIP_CLEAR, regs + K210_SYSCTL_PLL_LOCK); + } + + k210_set_bits(PLL_OUT_EN, regs + K210_SYSCTL_PLL1); +} + +static unsigned long k210_sysctl_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct k210_sysctl *s = container_of(hw, struct k210_sysctl, hw); + u32 clksel0, pll0; + u64 pll0_freq, clkr0, clkf0, clkod0; + + /* + * If the clock selector is not set, use the base frequency. + * Otherwise, use PLL0 frequency with a frequency divisor. + */ + clksel0 = readl(s->regs + K210_SYSCTL_CLKSEL0); + if (!(clksel0 & CLKSEL_ACLK)) + return K210_SYSCTL_CLK0_FREQ; + + /* + * Get PLL0 frequency: + * freq = base frequency * clkf0 / (clkr0 * clkod0) + */ + pll0 = readl(s->regs + K210_SYSCTL_PLL0); + clkr0 = 1 + FIELD_GET(GENMASK(3, 0), pll0); + clkf0 = 1 + FIELD_GET(GENMASK(9, 4), pll0); + clkod0 = 1 + FIELD_GET(GENMASK(13, 10), pll0); + pll0_freq = clkf0 * K210_SYSCTL_CLK0_FREQ / (clkr0 * clkod0); + + /* Get the frequency divisor from the clock selector */ + return pll0_freq / (2ULL << FIELD_GET(0x00000006, clksel0)); +} + +static const struct clk_ops k210_sysctl_clk_ops = { + .recalc_rate = k210_sysctl_clk_recalc_rate, +}; + +static const struct clk_init_data k210_clk_init_data = { + .name = "k210-sysctl-pll1", + .ops = &k210_sysctl_clk_ops, +}; + +static int k210_sysctl_probe(struct platform_device *pdev) +{ + struct k210_sysctl *s; + int error; + + pr_info("Kendryte K210 SoC sysctl\n"); + + s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL); + if (!s) + return -ENOMEM; + + s->regs = devm_ioremap_resource(&pdev->dev, + platform_get_resource(pdev, IORESOURCE_MEM, 0)); + if (IS_ERR(s->regs)) + return PTR_ERR(s->regs); + + s->hw.init = &k210_clk_init_data; + error = devm_clk_hw_register(&pdev->dev, &s->hw); + if (error) { + dev_err(&pdev->dev, "failed to register clk"); + return error; + } + + error = devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get, + &s->hw); + if (error) { + dev_err(&pdev->dev, "adding clk provider failed\n"); + return error; + } + + return 0; +} + +static const struct of_device_id k210_sysctl_of_match[] = { + { .compatible = "kendryte,k210-sysctl", }, + {} +}; + +static struct platform_driver k210_sysctl_driver = { + .driver = { + .name = "k210-sysctl", + .of_match_table = k210_sysctl_of_match, + }, + .probe = k210_sysctl_probe, +}; + +static int __init k210_sysctl_init(void) +{ + return platform_driver_register(&k210_sysctl_driver); +} +core_initcall(k210_sysctl_init); + +/* + * This needs to be called very early during initialization, given that + * PLL1 needs to be enabled to be able to use all SRAM. + */ +static void __init k210_soc_early_init(const void *fdt) +{ + void __iomem *regs; + + regs = ioremap(K210_SYSCTL_SYSCTL_BASE_ADDR, 0x1000); + if (!regs) + panic("K210 sysctl ioremap"); + + /* Enable PLL1 to make the KPU SRAM useable */ + k210_pll1_enable(regs); + + k210_set_bits(PLL_OUT_EN, regs + K210_SYSCTL_PLL0); + + k210_set_bits(CLKEN_CPU | CLKEN_SRAM0 | CLKEN_SRAM1, + regs + K210_SYSCTL_CLKEN_CENT); + k210_set_bits(CLKEN_ROM | CLKEN_TIMER0 | CLKEN_RTC, + regs + K210_SYSCTL_CLKEN_PERI); + + k210_set_bits(CLKSEL_ACLK, regs + K210_SYSCTL_CLKSEL0); + + iounmap(regs); +} +SOC_EARLY_INIT_DECLARE(generic_k210, "kendryte,k210", k210_soc_early_init); |