1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Marvell PXA family clocks 4 * 5 * Copyright (C) 2014 Robert Jarzmik 6 * 7 * Common clock code for PXA clocks ("CKEN" type clocks + DT) 8 */ 9 #include <linux/clk.h> 10 #include <linux/clk-provider.h> 11 #include <linux/clkdev.h> 12 #include <linux/io.h> 13 #include <linux/of.h> 14 #include <linux/soc/pxa/smemc.h> 15 16 #include <dt-bindings/clock/pxa-clock.h> 17 #include "clk-pxa.h" 18 19 #define KHz 1000 20 #define MHz (1000 * 1000) 21 22 #define MDREFR_K0DB4 (1 << 29) /* SDCLK0 Divide by 4 Control/Status */ 23 #define MDREFR_K2FREE (1 << 25) /* SDRAM Free-Running Control */ 24 #define MDREFR_K1FREE (1 << 24) /* SDRAM Free-Running Control */ 25 #define MDREFR_K0FREE (1 << 23) /* SDRAM Free-Running Control */ 26 #define MDREFR_SLFRSH (1 << 22) /* SDRAM Self-Refresh Control/Status */ 27 #define MDREFR_APD (1 << 20) /* SDRAM/SSRAM Auto-Power-Down Enable */ 28 #define MDREFR_K2DB2 (1 << 19) /* SDCLK2 Divide by 2 Control/Status */ 29 #define MDREFR_K2RUN (1 << 18) /* SDCLK2 Run Control/Status */ 30 #define MDREFR_K1DB2 (1 << 17) /* SDCLK1 Divide by 2 Control/Status */ 31 #define MDREFR_K1RUN (1 << 16) /* SDCLK1 Run Control/Status */ 32 #define MDREFR_E1PIN (1 << 15) /* SDCKE1 Level Control/Status */ 33 #define MDREFR_K0DB2 (1 << 14) /* SDCLK0 Divide by 2 Control/Status */ 34 #define MDREFR_K0RUN (1 << 13) /* SDCLK0 Run Control/Status */ 35 #define MDREFR_E0PIN (1 << 12) /* SDCKE0 Level Control/Status */ 36 #define MDREFR_DB2_MASK (MDREFR_K2DB2 | MDREFR_K1DB2) 37 #define MDREFR_DRI_MASK 0xFFF 38 39 static DEFINE_SPINLOCK(pxa_clk_lock); 40 41 static struct clk *pxa_clocks[CLK_MAX]; 42 static struct clk_onecell_data onecell_data = { 43 .clks = pxa_clocks, 44 .clk_num = CLK_MAX, 45 }; 46 47 struct pxa_clk { 48 struct clk_hw hw; 49 struct clk_fixed_factor lp; 50 struct clk_fixed_factor hp; 51 struct clk_gate gate; 52 bool (*is_in_low_power)(void); 53 }; 54 55 #define to_pxa_clk(_hw) container_of(_hw, struct pxa_clk, hw) 56 57 static unsigned long cken_recalc_rate(struct clk_hw *hw, 58 unsigned long parent_rate) 59 { 60 struct pxa_clk *pclk = to_pxa_clk(hw); 61 struct clk_fixed_factor *fix; 62 63 if (!pclk->is_in_low_power || pclk->is_in_low_power()) 64 fix = &pclk->lp; 65 else 66 fix = &pclk->hp; 67 __clk_hw_set_clk(&fix->hw, hw); 68 return clk_fixed_factor_ops.recalc_rate(&fix->hw, parent_rate); 69 } 70 71 static const struct clk_ops cken_rate_ops = { 72 .recalc_rate = cken_recalc_rate, 73 }; 74 75 static u8 cken_get_parent(struct clk_hw *hw) 76 { 77 struct pxa_clk *pclk = to_pxa_clk(hw); 78 79 if (!pclk->is_in_low_power) 80 return 0; 81 return pclk->is_in_low_power() ? 0 : 1; 82 } 83 84 static const struct clk_ops cken_mux_ops = { 85 .get_parent = cken_get_parent, 86 .set_parent = dummy_clk_set_parent, 87 }; 88 89 void __init clkdev_pxa_register(int ckid, const char *con_id, 90 const char *dev_id, struct clk *clk) 91 { 92 if (!IS_ERR(clk) && (ckid != CLK_NONE)) 93 pxa_clocks[ckid] = clk; 94 if (!IS_ERR(clk)) 95 clk_register_clkdev(clk, con_id, dev_id); 96 } 97 98 int __init clk_pxa_cken_init(const struct desc_clk_cken *clks, 99 int nb_clks, void __iomem *clk_regs) 100 { 101 int i; 102 struct pxa_clk *pxa_clk; 103 struct clk *clk; 104 105 for (i = 0; i < nb_clks; i++) { 106 pxa_clk = kzalloc(sizeof(*pxa_clk), GFP_KERNEL); 107 if (!pxa_clk) 108 return -ENOMEM; 109 pxa_clk->is_in_low_power = clks[i].is_in_low_power; 110 pxa_clk->lp = clks[i].lp; 111 pxa_clk->hp = clks[i].hp; 112 pxa_clk->gate = clks[i].gate; 113 pxa_clk->gate.reg = clk_regs + clks[i].cken_reg; 114 pxa_clk->gate.lock = &pxa_clk_lock; 115 clk = clk_register_composite(NULL, clks[i].name, 116 clks[i].parent_names, 2, 117 &pxa_clk->hw, &cken_mux_ops, 118 &pxa_clk->hw, &cken_rate_ops, 119 &pxa_clk->gate.hw, &clk_gate_ops, 120 clks[i].flags); 121 clkdev_pxa_register(clks[i].ckid, clks[i].con_id, 122 clks[i].dev_id, clk); 123 } 124 return 0; 125 } 126 127 void __init clk_pxa_dt_common_init(struct device_node *np) 128 { 129 of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data); 130 } 131 132 void pxa2xx_core_turbo_switch(bool on) 133 { 134 unsigned long flags; 135 unsigned int unused, clkcfg; 136 137 local_irq_save(flags); 138 139 asm("mrc p14, 0, %0, c6, c0, 0" : "=r" (clkcfg)); 140 clkcfg &= ~CLKCFG_TURBO & ~CLKCFG_HALFTURBO; 141 if (on) 142 clkcfg |= CLKCFG_TURBO; 143 clkcfg |= CLKCFG_FCS; 144 145 asm volatile( 146 " b 2f\n" 147 " .align 5\n" 148 "1: mcr p14, 0, %1, c6, c0, 0\n" 149 " b 3f\n" 150 "2: b 1b\n" 151 "3: nop\n" 152 : "=&r" (unused) : "r" (clkcfg)); 153 154 local_irq_restore(flags); 155 } 156 157 void pxa2xx_cpll_change(struct pxa2xx_freq *freq, 158 u32 (*mdrefr_dri)(unsigned int), 159 void __iomem *cccr) 160 { 161 unsigned int clkcfg = freq->clkcfg; 162 unsigned int unused, preset_mdrefr, postset_mdrefr; 163 unsigned long flags; 164 void __iomem *mdrefr = pxa_smemc_get_mdrefr(); 165 166 local_irq_save(flags); 167 168 /* Calculate the next MDREFR. If we're slowing down the SDRAM clock 169 * we need to preset the smaller DRI before the change. If we're 170 * speeding up we need to set the larger DRI value after the change. 171 */ 172 preset_mdrefr = postset_mdrefr = readl(mdrefr); 173 if ((preset_mdrefr & MDREFR_DRI_MASK) > mdrefr_dri(freq->membus_khz)) { 174 preset_mdrefr = (preset_mdrefr & ~MDREFR_DRI_MASK); 175 preset_mdrefr |= mdrefr_dri(freq->membus_khz); 176 } 177 postset_mdrefr = 178 (postset_mdrefr & ~MDREFR_DRI_MASK) | 179 mdrefr_dri(freq->membus_khz); 180 181 /* If we're dividing the memory clock by two for the SDRAM clock, this 182 * must be set prior to the change. Clearing the divide must be done 183 * after the change. 184 */ 185 if (freq->div2) { 186 preset_mdrefr |= MDREFR_DB2_MASK; 187 postset_mdrefr |= MDREFR_DB2_MASK; 188 } else { 189 postset_mdrefr &= ~MDREFR_DB2_MASK; 190 } 191 192 /* Set new the CCCR and prepare CLKCFG */ 193 writel(freq->cccr, cccr); 194 195 asm volatile( 196 " ldr r4, [%1]\n" 197 " b 2f\n" 198 " .align 5\n" 199 "1: str %3, [%1] /* preset the MDREFR */\n" 200 " mcr p14, 0, %2, c6, c0, 0 /* set CLKCFG[FCS] */\n" 201 " str %4, [%1] /* postset the MDREFR */\n" 202 " b 3f\n" 203 "2: b 1b\n" 204 "3: nop\n" 205 : "=&r" (unused) 206 : "r" (mdrefr), "r" (clkcfg), "r" (preset_mdrefr), 207 "r" (postset_mdrefr) 208 : "r4", "r5"); 209 210 local_irq_restore(flags); 211 } 212 213 int pxa2xx_determine_rate(struct clk_rate_request *req, 214 struct pxa2xx_freq *freqs, int nb_freqs) 215 { 216 int i, closest_below = -1, closest_above = -1; 217 unsigned long rate; 218 219 for (i = 0; i < nb_freqs; i++) { 220 rate = freqs[i].cpll; 221 if (rate == req->rate) 222 break; 223 if (rate < req->min_rate) 224 continue; 225 if (rate > req->max_rate) 226 continue; 227 if (rate <= req->rate) 228 closest_below = i; 229 if ((rate >= req->rate) && (closest_above == -1)) 230 closest_above = i; 231 } 232 233 req->best_parent_hw = NULL; 234 235 if (i < nb_freqs) { 236 rate = req->rate; 237 } else if (closest_below >= 0) { 238 rate = freqs[closest_below].cpll; 239 } else if (closest_above >= 0) { 240 rate = freqs[closest_above].cpll; 241 } else { 242 pr_debug("%s(rate=%lu) no match\n", __func__, req->rate); 243 return -EINVAL; 244 } 245 246 pr_debug("%s(rate=%lu) rate=%lu\n", __func__, req->rate, rate); 247 req->rate = rate; 248 249 return 0; 250 } 251