diff options
Diffstat (limited to 'drivers/clk/axis')
| -rw-r--r-- | drivers/clk/axis/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clk/axis/clk-artpec6.c | 242 |
2 files changed, 243 insertions, 0 deletions
diff --git a/drivers/clk/axis/Makefile b/drivers/clk/axis/Makefile new file mode 100644 index 000000000..628c9d3b9 --- /dev/null +++ b/drivers/clk/axis/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_MACH_ARTPEC6) += clk-artpec6.o diff --git a/drivers/clk/axis/clk-artpec6.c b/drivers/clk/axis/clk-artpec6.c new file mode 100644 index 000000000..da1a073c2 --- /dev/null +++ b/drivers/clk/axis/clk-artpec6.c @@ -0,0 +1,242 @@ +/* + * ARTPEC-6 clock initialization + * + * Copyright 2015-2016 Axis Comunications AB. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <dt-bindings/clock/axis,artpec6-clkctrl.h> + +#define NUM_I2S_CLOCKS 2 + +struct artpec6_clkctrl_drvdata { + struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS]; + void __iomem *syscon_base; + struct clk_onecell_data clk_data; + spinlock_t i2scfg_lock; +}; + +static struct artpec6_clkctrl_drvdata *clkdata; + +static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = { + "i2s0", + "i2s1", +}; + +static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = { + ARTPEC6_CLK_I2S0_CLK, + ARTPEC6_CLK_I2S1_CLK, +}; + +static void of_artpec6_clkctrl_setup(struct device_node *np) +{ + int i; + const char *sys_refclk_name; + u32 pll_mode, pll_m, pll_n; + struct clk **clks; + + /* Mandatory parent clock. */ + i = of_property_match_string(np, "clock-names", "sys_refclk"); + if (i < 0) + return; + + sys_refclk_name = of_clk_get_parent_name(np, i); + + clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL); + if (!clkdata) + return; + + clks = clkdata->clk_table; + + for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) + clks[i] = ERR_PTR(-EPROBE_DEFER); + + clkdata->syscon_base = of_iomap(np, 0); + BUG_ON(clkdata->syscon_base == NULL); + + /* Read PLL1 factors configured by boot strap pins. */ + pll_mode = (readl(clkdata->syscon_base) >> 6) & 3; + switch (pll_mode) { + case 0: /* DDR3-2133 mode */ + pll_m = 4; + pll_n = 85; + break; + case 1: /* DDR3-1866 mode */ + pll_m = 6; + pll_n = 112; + break; + case 2: /* DDR3-1600 mode */ + pll_m = 4; + pll_n = 64; + break; + case 3: /* DDR3-1333 mode */ + pll_m = 8; + pll_n = 106; + break; + } + + clks[ARTPEC6_CLK_CPU] = + clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n, + pll_m); + clks[ARTPEC6_CLK_CPU_PERIPH] = + clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2); + + /* EPROBE_DEFER on the apb_clock is not handled in amba devices. */ + clks[ARTPEC6_CLK_UART_PCLK] = + clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8); + clks[ARTPEC6_CLK_UART_REFCLK] = + clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0, + 50000000); + + clks[ARTPEC6_CLK_SPI_PCLK] = + clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8); + clks[ARTPEC6_CLK_SPI_SSPCLK] = + clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0, + 50000000); + + clks[ARTPEC6_CLK_DBG_PCLK] = + clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8); + + clkdata->clk_data.clks = clkdata->clk_table; + clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS; + + of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data); +} + +CLK_OF_DECLARE_DRIVER(artpec6_clkctrl, "axis,artpec6-clkctrl", + of_artpec6_clkctrl_setup); + +static int artpec6_clkctrl_probe(struct platform_device *pdev) +{ + int propidx; + struct device_node *np = pdev->dev.of_node; + struct device *dev = &pdev->dev; + struct clk **clks = clkdata->clk_table; + const char *sys_refclk_name; + const char *i2s_refclk_name = NULL; + const char *frac_clk_name[2] = { NULL, NULL }; + const char *i2s_mux_parents[2]; + u32 muxreg; + int i; + int err = 0; + + /* Mandatory parent clock. */ + propidx = of_property_match_string(np, "clock-names", "sys_refclk"); + if (propidx < 0) + return -EINVAL; + + sys_refclk_name = of_clk_get_parent_name(np, propidx); + + /* Find clock names of optional parent clocks. */ + propidx = of_property_match_string(np, "clock-names", "i2s_refclk"); + if (propidx >= 0) + i2s_refclk_name = of_clk_get_parent_name(np, propidx); + + propidx = of_property_match_string(np, "clock-names", "frac_clk0"); + if (propidx >= 0) + frac_clk_name[0] = of_clk_get_parent_name(np, propidx); + propidx = of_property_match_string(np, "clock-names", "frac_clk1"); + if (propidx >= 0) + frac_clk_name[1] = of_clk_get_parent_name(np, propidx); + + spin_lock_init(&clkdata->i2scfg_lock); + + clks[ARTPEC6_CLK_NAND_CLKA] = + clk_register_fixed_factor(dev, "nand_clka", "cpu", 0, 1, 8); + clks[ARTPEC6_CLK_NAND_CLKB] = + clk_register_fixed_rate(dev, "nand_clkb", sys_refclk_name, 0, + 100000000); + clks[ARTPEC6_CLK_ETH_ACLK] = + clk_register_fixed_factor(dev, "eth_aclk", "cpu", 0, 1, 4); + clks[ARTPEC6_CLK_DMA_ACLK] = + clk_register_fixed_factor(dev, "dma_aclk", "cpu", 0, 1, 4); + clks[ARTPEC6_CLK_PTP_REF] = + clk_register_fixed_rate(dev, "ptp_ref", sys_refclk_name, 0, + 100000000); + clks[ARTPEC6_CLK_SD_PCLK] = + clk_register_fixed_rate(dev, "sd_pclk", sys_refclk_name, 0, + 100000000); + clks[ARTPEC6_CLK_SD_IMCLK] = + clk_register_fixed_rate(dev, "sd_imclk", sys_refclk_name, 0, + 100000000); + clks[ARTPEC6_CLK_I2S_HST] = + clk_register_fixed_factor(dev, "i2s_hst", "cpu", 0, 1, 8); + + for (i = 0; i < NUM_I2S_CLOCKS; ++i) { + if (i2s_refclk_name && frac_clk_name[i]) { + i2s_mux_parents[0] = frac_clk_name[i]; + i2s_mux_parents[1] = i2s_refclk_name; + + clks[i2s_clk_indexes[i]] = + clk_register_mux(dev, i2s_clk_names[i], + i2s_mux_parents, 2, + CLK_SET_RATE_NO_REPARENT | + CLK_SET_RATE_PARENT, + clkdata->syscon_base + 0x14, i, 1, + 0, &clkdata->i2scfg_lock); + } else if (frac_clk_name[i]) { + /* Lock the mux for internal clock reference. */ + muxreg = readl(clkdata->syscon_base + 0x14); + muxreg &= ~BIT(i); + writel(muxreg, clkdata->syscon_base + 0x14); + clks[i2s_clk_indexes[i]] = + clk_register_fixed_factor(dev, i2s_clk_names[i], + frac_clk_name[i], 0, 1, + 1); + } else if (i2s_refclk_name) { + /* Lock the mux for external clock reference. */ + muxreg = readl(clkdata->syscon_base + 0x14); + muxreg |= BIT(i); + writel(muxreg, clkdata->syscon_base + 0x14); + clks[i2s_clk_indexes[i]] = + clk_register_fixed_factor(dev, i2s_clk_names[i], + i2s_refclk_name, 0, 1, 1); + } + } + + clks[ARTPEC6_CLK_I2C] = + clk_register_fixed_rate(dev, "i2c", sys_refclk_name, 0, 100000000); + + clks[ARTPEC6_CLK_SYS_TIMER] = + clk_register_fixed_rate(dev, "timer", sys_refclk_name, 0, + 100000000); + clks[ARTPEC6_CLK_FRACDIV_IN] = + clk_register_fixed_rate(dev, "fracdiv_in", sys_refclk_name, 0, + 600000000); + + for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) { + if (IS_ERR(clks[i]) && PTR_ERR(clks[i]) != -EPROBE_DEFER) { + dev_err(dev, + "Failed to register clock at index %d err=%ld\n", + i, PTR_ERR(clks[i])); + err = PTR_ERR(clks[i]); + } + } + + return err; +} + +static const struct of_device_id artpec_clkctrl_of_match[] = { + { .compatible = "axis,artpec6-clkctrl" }, + {} +}; + +static struct platform_driver artpec6_clkctrl_driver = { + .probe = artpec6_clkctrl_probe, + .driver = { + .name = "artpec6_clkctrl", + .of_match_table = artpec_clkctrl_of_match, + }, +}; + +builtin_platform_driver(artpec6_clkctrl_driver); |