1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ARTPEC-6 clock initialization 4 * 5 * Copyright 2015-2016 Axis Communications AB. 6 */ 7 8 #include <linux/clk-provider.h> 9 #include <linux/device.h> 10 #include <linux/io.h> 11 #include <linux/of.h> 12 #include <linux/of_address.h> 13 #include <linux/platform_device.h> 14 #include <linux/slab.h> 15 #include <dt-bindings/clock/axis,artpec6-clkctrl.h> 16 17 #define NUM_I2S_CLOCKS 2 18 19 struct artpec6_clkctrl_drvdata { 20 struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS]; 21 void __iomem *syscon_base; 22 struct clk_onecell_data clk_data; 23 spinlock_t i2scfg_lock; 24 }; 25 26 static struct artpec6_clkctrl_drvdata *clkdata; 27 28 static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = { 29 "i2s0", 30 "i2s1", 31 }; 32 33 static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = { 34 ARTPEC6_CLK_I2S0_CLK, 35 ARTPEC6_CLK_I2S1_CLK, 36 }; 37 38 static void of_artpec6_clkctrl_setup(struct device_node *np) 39 { 40 int i; 41 const char *sys_refclk_name; 42 u32 pll_mode, pll_m, pll_n; 43 struct clk **clks; 44 45 /* Mandatory parent clock. */ 46 i = of_property_match_string(np, "clock-names", "sys_refclk"); 47 if (i < 0) 48 return; 49 50 sys_refclk_name = of_clk_get_parent_name(np, i); 51 52 clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL); 53 if (!clkdata) 54 return; 55 56 clks = clkdata->clk_table; 57 58 for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) 59 clks[i] = ERR_PTR(-EPROBE_DEFER); 60 61 clkdata->syscon_base = of_iomap(np, 0); 62 BUG_ON(clkdata->syscon_base == NULL); 63 64 /* Read PLL1 factors configured by boot strap pins. */ 65 pll_mode = (readl(clkdata->syscon_base) >> 6) & 3; 66 switch (pll_mode) { 67 case 0: /* DDR3-2133 mode */ 68 pll_m = 4; 69 pll_n = 85; 70 break; 71 case 1: /* DDR3-1866 mode */ 72 pll_m = 6; 73 pll_n = 112; 74 break; 75 case 2: /* DDR3-1600 mode */ 76 pll_m = 4; 77 pll_n = 64; 78 break; 79 case 3: /* DDR3-1333 mode */ 80 pll_m = 8; 81 pll_n = 106; 82 break; 83 } 84 85 clks[ARTPEC6_CLK_CPU] = 86 clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n, 87 pll_m); 88 clks[ARTPEC6_CLK_CPU_PERIPH] = 89 clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2); 90 91 /* EPROBE_DEFER on the apb_clock is not handled in amba devices. */ 92 clks[ARTPEC6_CLK_UART_PCLK] = 93 clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8); 94 clks[ARTPEC6_CLK_UART_REFCLK] = 95 clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0, 96 50000000); 97 98 clks[ARTPEC6_CLK_SPI_PCLK] = 99 clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8); 100 clks[ARTPEC6_CLK_SPI_SSPCLK] = 101 clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0, 102 50000000); 103 104 clks[ARTPEC6_CLK_DBG_PCLK] = 105 clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8); 106 107 clkdata->clk_data.clks = clkdata->clk_table; 108 clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS; 109 110 of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data); 111 } 112 113 CLK_OF_DECLARE_DRIVER(artpec6_clkctrl, "axis,artpec6-clkctrl", 114 of_artpec6_clkctrl_setup); 115 116 static int artpec6_clkctrl_probe(struct platform_device *pdev) 117 { 118 int propidx; 119 struct device_node *np = pdev->dev.of_node; 120 struct device *dev = &pdev->dev; 121 struct clk **clks = clkdata->clk_table; 122 const char *sys_refclk_name; 123 const char *i2s_refclk_name = NULL; 124 const char *frac_clk_name[2] = { NULL, NULL }; 125 const char *i2s_mux_parents[2]; 126 u32 muxreg; 127 int i; 128 int err = 0; 129 130 /* Mandatory parent clock. */ 131 propidx = of_property_match_string(np, "clock-names", "sys_refclk"); 132 if (propidx < 0) 133 return -EINVAL; 134 135 sys_refclk_name = of_clk_get_parent_name(np, propidx); 136 137 /* Find clock names of optional parent clocks. */ 138 propidx = of_property_match_string(np, "clock-names", "i2s_refclk"); 139 if (propidx >= 0) 140 i2s_refclk_name = of_clk_get_parent_name(np, propidx); 141 142 propidx = of_property_match_string(np, "clock-names", "frac_clk0"); 143 if (propidx >= 0) 144 frac_clk_name[0] = of_clk_get_parent_name(np, propidx); 145 propidx = of_property_match_string(np, "clock-names", "frac_clk1"); 146 if (propidx >= 0) 147 frac_clk_name[1] = of_clk_get_parent_name(np, propidx); 148 149 spin_lock_init(&clkdata->i2scfg_lock); 150 151 clks[ARTPEC6_CLK_NAND_CLKA] = 152 clk_register_fixed_factor(dev, "nand_clka", "cpu", 0, 1, 8); 153 clks[ARTPEC6_CLK_NAND_CLKB] = 154 clk_register_fixed_rate(dev, "nand_clkb", sys_refclk_name, 0, 155 100000000); 156 clks[ARTPEC6_CLK_ETH_ACLK] = 157 clk_register_fixed_factor(dev, "eth_aclk", "cpu", 0, 1, 4); 158 clks[ARTPEC6_CLK_DMA_ACLK] = 159 clk_register_fixed_factor(dev, "dma_aclk", "cpu", 0, 1, 4); 160 clks[ARTPEC6_CLK_PTP_REF] = 161 clk_register_fixed_rate(dev, "ptp_ref", sys_refclk_name, 0, 162 100000000); 163 clks[ARTPEC6_CLK_SD_PCLK] = 164 clk_register_fixed_rate(dev, "sd_pclk", sys_refclk_name, 0, 165 100000000); 166 clks[ARTPEC6_CLK_SD_IMCLK] = 167 clk_register_fixed_rate(dev, "sd_imclk", sys_refclk_name, 0, 168 100000000); 169 clks[ARTPEC6_CLK_I2S_HST] = 170 clk_register_fixed_factor(dev, "i2s_hst", "cpu", 0, 1, 8); 171 172 for (i = 0; i < NUM_I2S_CLOCKS; ++i) { 173 if (i2s_refclk_name && frac_clk_name[i]) { 174 i2s_mux_parents[0] = frac_clk_name[i]; 175 i2s_mux_parents[1] = i2s_refclk_name; 176 177 clks[i2s_clk_indexes[i]] = 178 clk_register_mux(dev, i2s_clk_names[i], 179 i2s_mux_parents, 2, 180 CLK_SET_RATE_NO_REPARENT | 181 CLK_SET_RATE_PARENT, 182 clkdata->syscon_base + 0x14, i, 1, 183 0, &clkdata->i2scfg_lock); 184 } else if (frac_clk_name[i]) { 185 /* Lock the mux for internal clock reference. */ 186 muxreg = readl(clkdata->syscon_base + 0x14); 187 muxreg &= ~BIT(i); 188 writel(muxreg, clkdata->syscon_base + 0x14); 189 clks[i2s_clk_indexes[i]] = 190 clk_register_fixed_factor(dev, i2s_clk_names[i], 191 frac_clk_name[i], 0, 1, 192 1); 193 } else if (i2s_refclk_name) { 194 /* Lock the mux for external clock reference. */ 195 muxreg = readl(clkdata->syscon_base + 0x14); 196 muxreg |= BIT(i); 197 writel(muxreg, clkdata->syscon_base + 0x14); 198 clks[i2s_clk_indexes[i]] = 199 clk_register_fixed_factor(dev, i2s_clk_names[i], 200 i2s_refclk_name, 0, 1, 1); 201 } 202 } 203 204 clks[ARTPEC6_CLK_I2C] = 205 clk_register_fixed_rate(dev, "i2c", sys_refclk_name, 0, 100000000); 206 207 clks[ARTPEC6_CLK_SYS_TIMER] = 208 clk_register_fixed_rate(dev, "timer", sys_refclk_name, 0, 209 100000000); 210 clks[ARTPEC6_CLK_FRACDIV_IN] = 211 clk_register_fixed_rate(dev, "fracdiv_in", sys_refclk_name, 0, 212 600000000); 213 214 for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) { 215 if (IS_ERR(clks[i]) && PTR_ERR(clks[i]) != -EPROBE_DEFER) { 216 dev_err(dev, 217 "Failed to register clock at index %d err=%ld\n", 218 i, PTR_ERR(clks[i])); 219 err = PTR_ERR(clks[i]); 220 } 221 } 222 223 return err; 224 } 225 226 static const struct of_device_id artpec_clkctrl_of_match[] = { 227 { .compatible = "axis,artpec6-clkctrl" }, 228 {} 229 }; 230 231 static struct platform_driver artpec6_clkctrl_driver = { 232 .probe = artpec6_clkctrl_probe, 233 .driver = { 234 .name = "artpec6_clkctrl", 235 .of_match_table = artpec_clkctrl_of_match, 236 }, 237 }; 238 239 builtin_platform_driver(artpec6_clkctrl_driver); 240