1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/bits.h> 3 #include <linux/clk.h> 4 #include <linux/clk-provider.h> 5 #include <linux/err.h> 6 #include <linux/io.h> 7 #include <linux/module.h> 8 #include <linux/of.h> 9 #include <linux/slab.h> 10 #include <linux/spinlock.h> 11 #include "clk.h" 12 13 #define CCM_CCDR 0x4 14 #define CCDR_MMDC_CH0_MASK BIT(17) 15 #define CCDR_MMDC_CH1_MASK BIT(16) 16 17 DEFINE_SPINLOCK(imx_ccm_lock); 18 EXPORT_SYMBOL_GPL(imx_ccm_lock); 19 20 bool mcore_booted; 21 EXPORT_SYMBOL_GPL(mcore_booted); 22 23 void imx_unregister_clocks(struct clk *clks[], unsigned int count) 24 { 25 unsigned int i; 26 27 for (i = 0; i < count; i++) 28 clk_unregister(clks[i]); 29 } 30 31 void imx_unregister_hw_clocks(struct clk_hw *hws[], unsigned int count) 32 { 33 unsigned int i; 34 35 for (i = 0; i < count; i++) 36 clk_hw_unregister(hws[i]); 37 } 38 EXPORT_SYMBOL_GPL(imx_unregister_hw_clocks); 39 40 void imx_mmdc_mask_handshake(void __iomem *ccm_base, 41 unsigned int chn) 42 { 43 unsigned int reg; 44 45 reg = readl_relaxed(ccm_base + CCM_CCDR); 46 reg |= chn == 0 ? CCDR_MMDC_CH0_MASK : CCDR_MMDC_CH1_MASK; 47 writel_relaxed(reg, ccm_base + CCM_CCDR); 48 } 49 50 void imx_check_clocks(struct clk *clks[], unsigned int count) 51 { 52 unsigned i; 53 54 for (i = 0; i < count; i++) 55 if (IS_ERR(clks[i])) 56 pr_err("i.MX clk %u: register failed with %ld\n", 57 i, PTR_ERR(clks[i])); 58 } 59 60 void imx_check_clk_hws(struct clk_hw *clks[], unsigned int count) 61 { 62 unsigned int i; 63 64 for (i = 0; i < count; i++) 65 if (IS_ERR(clks[i])) 66 pr_err("i.MX clk %u: register failed with %ld\n", 67 i, PTR_ERR(clks[i])); 68 } 69 EXPORT_SYMBOL_GPL(imx_check_clk_hws); 70 71 static struct clk *imx_obtain_fixed_clock_from_dt(const char *name) 72 { 73 struct of_phandle_args phandle; 74 struct clk *clk = ERR_PTR(-ENODEV); 75 char *path; 76 77 path = kasprintf(GFP_KERNEL, "/clocks/%s", name); 78 if (!path) 79 return ERR_PTR(-ENOMEM); 80 81 phandle.np = of_find_node_by_path(path); 82 kfree(path); 83 84 if (phandle.np) { 85 clk = of_clk_get_from_provider(&phandle); 86 of_node_put(phandle.np); 87 } 88 return clk; 89 } 90 91 struct clk *imx_obtain_fixed_clock( 92 const char *name, unsigned long rate) 93 { 94 struct clk *clk; 95 96 clk = imx_obtain_fixed_clock_from_dt(name); 97 if (IS_ERR(clk)) 98 clk = imx_clk_fixed(name, rate); 99 return clk; 100 } 101 102 struct clk_hw *imx_obtain_fixed_clock_hw( 103 const char *name, unsigned long rate) 104 { 105 struct clk *clk; 106 107 clk = imx_obtain_fixed_clock_from_dt(name); 108 if (IS_ERR(clk)) 109 clk = imx_clk_fixed(name, rate); 110 return __clk_get_hw(clk); 111 } 112 113 struct clk_hw *imx_get_clk_hw_by_name(struct device_node *np, const char *name) 114 { 115 struct clk *clk; 116 117 clk = of_clk_get_by_name(np, name); 118 if (IS_ERR(clk)) 119 return ERR_PTR(-ENOENT); 120 121 return __clk_get_hw(clk); 122 } 123 EXPORT_SYMBOL_GPL(imx_get_clk_hw_by_name); 124 125 /* 126 * This fixups the register CCM_CSCMR1 write value. 127 * The write/read/divider values of the aclk_podf field 128 * of that register have the relationship described by 129 * the following table: 130 * 131 * write value read value divider 132 * 3b'000 3b'110 7 133 * 3b'001 3b'111 8 134 * 3b'010 3b'100 5 135 * 3b'011 3b'101 6 136 * 3b'100 3b'010 3 137 * 3b'101 3b'011 4 138 * 3b'110 3b'000 1 139 * 3b'111 3b'001 2(default) 140 * 141 * That's why we do the xor operation below. 142 */ 143 #define CSCMR1_FIXUP 0x00600000 144 145 void imx_cscmr1_fixup(u32 *val) 146 { 147 *val ^= CSCMR1_FIXUP; 148 return; 149 } 150 151 #ifndef MODULE 152 153 static bool imx_keep_uart_clocks; 154 static int imx_enabled_uart_clocks; 155 static struct clk **imx_uart_clocks; 156 157 static int __init imx_keep_uart_clocks_param(char *str) 158 { 159 imx_keep_uart_clocks = 1; 160 161 return 0; 162 } 163 __setup_param("earlycon", imx_keep_uart_earlycon, 164 imx_keep_uart_clocks_param, 0); 165 __setup_param("earlyprintk", imx_keep_uart_earlyprintk, 166 imx_keep_uart_clocks_param, 0); 167 168 void imx_register_uart_clocks(unsigned int clk_count) 169 { 170 imx_enabled_uart_clocks = 0; 171 172 /* i.MX boards use device trees now. For build tests without CONFIG_OF, do nothing */ 173 #ifdef CONFIG_OF 174 if (imx_keep_uart_clocks) { 175 int i; 176 177 imx_uart_clocks = kcalloc(clk_count, sizeof(struct clk *), GFP_KERNEL); 178 if (!imx_uart_clocks) 179 return; 180 181 if (!of_stdout) 182 return; 183 184 for (i = 0; i < clk_count; i++) { 185 imx_uart_clocks[imx_enabled_uart_clocks] = of_clk_get(of_stdout, i); 186 187 /* Stop if there are no more of_stdout references */ 188 if (IS_ERR(imx_uart_clocks[imx_enabled_uart_clocks])) 189 return; 190 191 /* Only enable the clock if it's not NULL */ 192 if (imx_uart_clocks[imx_enabled_uart_clocks]) 193 clk_prepare_enable(imx_uart_clocks[imx_enabled_uart_clocks++]); 194 } 195 } 196 #endif 197 } 198 199 static int __init imx_clk_disable_uart(void) 200 { 201 if (imx_keep_uart_clocks && imx_enabled_uart_clocks) { 202 int i; 203 204 for (i = 0; i < imx_enabled_uart_clocks; i++) { 205 clk_disable_unprepare(imx_uart_clocks[i]); 206 clk_put(imx_uart_clocks[i]); 207 } 208 } 209 210 kfree(imx_uart_clocks); 211 212 return 0; 213 } 214 late_initcall_sync(imx_clk_disable_uart); 215 #endif 216 217 MODULE_LICENSE("GPL v2"); 218