1 /* $OpenBSD: amlpwm.c,v 1.3 2021/10/24 17:52:26 mpi Exp $ */ 2 /* 3 * Copyright (c) 2019 Mark Kettenis <kettenis@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/param.h> 19 #include <sys/systm.h> 20 #include <sys/device.h> 21 22 #include <machine/intr.h> 23 #include <machine/bus.h> 24 #include <machine/fdt.h> 25 26 #include <dev/ofw/openfirm.h> 27 #include <dev/ofw/ofw_clock.h> 28 #include <dev/ofw/ofw_misc.h> 29 #include <dev/ofw/ofw_pinctrl.h> 30 #include <dev/ofw/fdt.h> 31 32 #define PWM_PWM_A 0x00 33 #define PWM_PWM_B 0x01 34 #define PWM_PWM_HIGH(x) ((x) >> 16) 35 #define PWM_PWM_HIGH_SHIFT 16 36 #define PWM_PWM_LOW(x) ((x) & 0xffff) 37 #define PWM_PWM_LOW_SHIFT 0 38 #define PWM_MISC_REG_AB 0x02 39 #define PWM_B_CLK_EN (1 << 23) 40 #define PWM_B_CLK_DIV_MASK (0x7f << 16) 41 #define PWM_B_CLK_DIV_SHIFT 16 42 #define PWM_B_CLK_DIV(x) ((((x) >> 16) & 0x7f) + 1) 43 #define PWM_A_CLK_EN (1 << 15) 44 #define PWM_A_CLK_DIV_MASK (0x7f << 8) 45 #define PWM_A_CLK_DIV_SHIFT 8 46 #define PWM_A_CLK_DIV(x) ((((x) >> 8) & 0x7f) + 1) 47 #define PWM_B_EN (1 << 1) 48 #define PWM_A_EN (1 << 0) 49 50 #define HREAD4(sc, reg) \ 51 (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg) << 2)) 52 #define HWRITE4(sc, reg, val) \ 53 bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg) << 2, (val)) 54 #define HSET4(sc, reg, bits) \ 55 HWRITE4((sc), (reg), HREAD4((sc), (reg)) | (bits)) 56 #define HCLR4(sc, reg, bits) \ 57 HWRITE4((sc), (reg), HREAD4((sc), (reg)) & ~(bits)) 58 59 struct amlpwm_softc { 60 struct device sc_dev; 61 bus_space_tag_t sc_iot; 62 bus_space_handle_t sc_ioh; 63 64 uint32_t sc_clkin[2]; 65 66 struct pwm_device sc_pd; 67 }; 68 69 int amlpwm_match(struct device *, void *, void *); 70 void amlpwm_attach(struct device *, struct device *, void *); 71 72 const struct cfattach amlpwm_ca = { 73 sizeof (struct amlpwm_softc), amlpwm_match, amlpwm_attach 74 }; 75 76 struct cfdriver amlpwm_cd = { 77 NULL, "amlpwm", DV_DULL 78 }; 79 80 int amlpwm_get_state(void *, uint32_t *, struct pwm_state *); 81 int amlpwm_set_state(void *, uint32_t *, struct pwm_state *); 82 83 int 84 amlpwm_match(struct device *parent, void *match, void *aux) 85 { 86 struct fdt_attach_args *faa = aux; 87 int node = faa->fa_node; 88 89 return (OF_is_compatible(node, "amlogic,meson-g12a-ao-pwm-cd") || 90 OF_is_compatible(node, "amlogic,meson-g12a-ee-pwm")); 91 } 92 93 void 94 amlpwm_attach(struct device *parent, struct device *self, void *aux) 95 { 96 struct amlpwm_softc *sc = (struct amlpwm_softc *)self; 97 struct fdt_attach_args *faa = aux; 98 99 if (faa->fa_nreg < 1) { 100 printf(": no registers\n"); 101 return; 102 } 103 104 sc->sc_iot = faa->fa_iot; 105 if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr, 106 faa->fa_reg[0].size, 0, &sc->sc_ioh)) { 107 printf(": can't map registers\n"); 108 return; 109 } 110 111 sc->sc_clkin[0] = clock_get_frequency(faa->fa_node, "clkin0"); 112 sc->sc_clkin[1] = clock_get_frequency(faa->fa_node, "clkin1"); 113 114 printf("\n"); 115 116 pinctrl_byname(faa->fa_node, "default"); 117 118 sc->sc_pd.pd_node = faa->fa_node; 119 sc->sc_pd.pd_cookie = sc; 120 sc->sc_pd.pd_get_state = amlpwm_get_state; 121 sc->sc_pd.pd_set_state = amlpwm_set_state; 122 pwm_register(&sc->sc_pd); 123 } 124 125 static inline uint32_t 126 cycles_to_ns(uint64_t clk_freq, uint32_t clk_div, uint32_t cycles) 127 { 128 return cycles * clk_div * 1000000000ULL / clk_freq; 129 } 130 131 static inline uint32_t 132 ns_to_cycles(uint64_t clk_freq, uint32_t clk_div, uint32_t ns) 133 { 134 return ns * clk_freq / (clk_div * 1000000000ULL); 135 } 136 137 int 138 amlpwm_get_state(void *cookie, uint32_t *cells, struct pwm_state *ps) 139 { 140 struct amlpwm_softc *sc = cookie; 141 uint32_t idx = cells[0]; 142 uint32_t pwm, misc; 143 uint32_t total, high; 144 uint32_t clk_div; 145 int enabled = 0; 146 147 if (idx > 1 || sc->sc_clkin[idx] == 0) 148 return EINVAL; 149 150 pwm = HREAD4(sc, idx == 0 ? PWM_PWM_A : PWM_PWM_B); 151 misc = HREAD4(sc, PWM_MISC_REG_AB); 152 153 if (idx == 0) { 154 if ((misc & PWM_A_CLK_EN) && (misc & PWM_A_EN)) 155 enabled = 1; 156 clk_div = PWM_A_CLK_DIV(misc); 157 } else { 158 if ((misc & PWM_B_CLK_EN) && (misc & PWM_B_EN)) 159 enabled = 1; 160 clk_div = PWM_B_CLK_DIV(misc); 161 } 162 163 total = PWM_PWM_LOW(pwm) + PWM_PWM_HIGH(pwm); 164 high = PWM_PWM_HIGH(pwm); 165 166 memset(ps, 0, sizeof(struct pwm_state)); 167 ps->ps_period = cycles_to_ns(sc->sc_clkin[idx], clk_div, total); 168 ps->ps_pulse_width = cycles_to_ns(sc->sc_clkin[idx], clk_div, high); 169 ps->ps_enabled = enabled; 170 171 return 0; 172 } 173 174 int 175 amlpwm_set_state(void *cookie, uint32_t *cells, struct pwm_state *ps) 176 { 177 struct amlpwm_softc *sc = cookie; 178 uint32_t idx = cells[0]; 179 uint32_t pwm, misc; 180 uint32_t total, high, low; 181 uint32_t clk_div = 1; 182 183 if (idx > 1 || sc->sc_clkin[idx] == 0) 184 return EINVAL; 185 186 /* Hardware doesn't support polarity inversion. */ 187 if (ps->ps_flags & PWM_POLARITY_INVERTED) 188 return EINVAL; 189 190 if (!ps->ps_enabled) { 191 HCLR4(sc, PWM_MISC_REG_AB, (idx == 0) ? PWM_A_EN : PWM_B_EN); 192 return 0; 193 } 194 195 total = ns_to_cycles(sc->sc_clkin[idx], clk_div, ps->ps_period); 196 while ((total / clk_div) > 0xffff) 197 clk_div++; 198 if (clk_div > 128) 199 return EINVAL; 200 201 total = ns_to_cycles(sc->sc_clkin[idx], clk_div, ps->ps_period); 202 high = ns_to_cycles(sc->sc_clkin[idx], clk_div, ps->ps_pulse_width); 203 low = total - high; 204 205 pwm = (high << PWM_PWM_HIGH_SHIFT) | (low << PWM_PWM_LOW_SHIFT); 206 misc = HREAD4(sc, PWM_MISC_REG_AB); 207 208 if (idx == 0) { 209 misc &= ~PWM_A_CLK_DIV_MASK; 210 misc |= (clk_div - 1) << PWM_A_CLK_DIV_SHIFT; 211 misc |= PWM_A_CLK_EN; 212 } else { 213 misc &= ~PWM_B_CLK_DIV_MASK; 214 misc |= (clk_div - 1) << PWM_B_CLK_DIV_SHIFT; 215 misc |= PWM_B_CLK_EN; 216 } 217 218 HWRITE4(sc, PWM_MISC_REG_AB, misc); 219 HWRITE4(sc, (idx == 0) ? PWM_PWM_A : PWM_PWM_B, pwm); 220 HSET4(sc, PWM_MISC_REG_AB, (idx == 0) ? PWM_A_EN : PWM_B_EN); 221 222 return 0; 223 } 224