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author | Christoph Hellwig <hch@lst.de> | 2020-03-16 09:47:39 +0900 |
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committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2020-04-03 10:49:52 -0700 |
commit | c48c4a4c7eadb76593965e2b956e4e2b23a4e388 (patch) | |
tree | 31be2ea1d5a0208300a07d9052f98beaf89c6395 /drivers/soc/kendryte | |
parent | 335b139057ef79dbede01dea6e8c3f47c2b88802 (diff) | |
download | linux-stable-c48c4a4c7eadb76593965e2b956e4e2b23a4e388.tar.gz linux-stable-c48c4a4c7eadb76593965e2b956e4e2b23a4e388.tar.bz2 linux-stable-c48c4a4c7eadb76593965e2b956e4e2b23a4e388.zip |
riscv: Add Kendryte K210 SoC support
Add support for the Kendryte K210 RISC-V SoC. For now, this support
only provides a simple sysctl driver allowing to setup the CPU and
uart clock. This support is enabled through the new Kconfig option
SOC_KENDRYTE and defines the config option CONFIG_K210_SYSCTL
to enable the K210 SoC sysctl driver compilation.
The sysctl driver also registers an early SoC initialization function
allowing enabling the general purpose use of the 2MB of SRAM normally
reserved for the SoC AI engine. This initialization function is
automatically called before the dt early initialization using the flat
dt root node compatible property matching the value "kendryte,k210".
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
[Palmer: Add missing endmenu in Kconfig.socs]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'drivers/soc/kendryte')
-rw-r--r-- | drivers/soc/kendryte/Kconfig | 14 | ||||
-rw-r--r-- | drivers/soc/kendryte/Makefile | 3 | ||||
-rw-r--r-- | drivers/soc/kendryte/k210-sysctl.c | 248 |
3 files changed, 265 insertions, 0 deletions
diff --git a/drivers/soc/kendryte/Kconfig b/drivers/soc/kendryte/Kconfig new file mode 100644 index 000000000000..49785b1b0217 --- /dev/null +++ b/drivers/soc/kendryte/Kconfig @@ -0,0 +1,14 @@ +# SPDX-License-Identifier: GPL-2.0 + +if SOC_KENDRYTE + +config K210_SYSCTL + bool "Kendryte K210 system controller" + default y + depends on RISCV + help + Enables controlling the K210 various clocks and to enable + general purpose use of the extra 2MB of SRAM normally + reserved for the AI engine. + +endif diff --git a/drivers/soc/kendryte/Makefile b/drivers/soc/kendryte/Makefile new file mode 100644 index 000000000000..002d9ce95c0d --- /dev/null +++ b/drivers/soc/kendryte/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_K210_SYSCTL) += k210-sysctl.o 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); |