1 /* 2 * Qualcomm SPMI bus driver 3 * 4 * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com> 5 * 6 * Loosely based on Little Kernel driver 7 * 8 * SPDX-License-Identifier: BSD-3-Clause 9 */ 10 11 #include <common.h> 12 #include <dm.h> 13 #include <errno.h> 14 #include <fdtdec.h> 15 #include <asm/io.h> 16 #include <spmi/spmi.h> 17 18 DECLARE_GLOBAL_DATA_PTR; 19 20 #define ARB_CHANNEL_OFFSET(n) (0x4 * (n)) 21 #define SPMI_CH_OFFSET(chnl) ((chnl) * 0x8000) 22 23 #define SPMI_REG_CMD0 0x0 24 #define SPMI_REG_CONFIG 0x4 25 #define SPMI_REG_STATUS 0x8 26 #define SPMI_REG_WDATA 0x10 27 #define SPMI_REG_RDATA 0x18 28 29 #define SPMI_CMD_OPCODE_SHIFT 27 30 #define SPMI_CMD_SLAVE_ID_SHIFT 20 31 #define SPMI_CMD_ADDR_SHIFT 12 32 #define SPMI_CMD_ADDR_OFFSET_SHIFT 4 33 #define SPMI_CMD_BYTE_CNT_SHIFT 0 34 35 #define SPMI_CMD_EXT_REG_WRITE_LONG 0x00 36 #define SPMI_CMD_EXT_REG_READ_LONG 0x01 37 38 #define SPMI_STATUS_DONE 0x1 39 40 #define SPMI_MAX_CHANNELS 128 41 #define SPMI_MAX_SLAVES 16 42 #define SPMI_MAX_PERIPH 256 43 44 struct msm_spmi_priv { 45 phys_addr_t arb_chnl; /* ARB channel mapping base */ 46 phys_addr_t spmi_core; /* SPMI core */ 47 phys_addr_t spmi_obs; /* SPMI observer */ 48 /* SPMI channel map */ 49 uint8_t channel_map[SPMI_MAX_SLAVES][SPMI_MAX_PERIPH]; 50 }; 51 52 static int msm_spmi_write(struct udevice *dev, int usid, int pid, int off, 53 uint8_t val) 54 { 55 struct msm_spmi_priv *priv = dev_get_priv(dev); 56 unsigned channel; 57 uint32_t reg = 0; 58 59 if (usid >= SPMI_MAX_SLAVES) 60 return -EIO; 61 if (pid >= SPMI_MAX_PERIPH) 62 return -EIO; 63 64 channel = priv->channel_map[usid][pid]; 65 66 /* Disable IRQ mode for the current channel*/ 67 writel(0x0, priv->spmi_core + SPMI_CH_OFFSET(channel) + 68 SPMI_REG_CONFIG); 69 70 /* Write single byte */ 71 writel(val, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_WDATA); 72 73 /* Prepare write command */ 74 reg |= SPMI_CMD_EXT_REG_WRITE_LONG << SPMI_CMD_OPCODE_SHIFT; 75 reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT); 76 reg |= (pid << SPMI_CMD_ADDR_SHIFT); 77 reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT); 78 reg |= 1; /* byte count */ 79 80 /* Send write command */ 81 writel(reg, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0); 82 83 /* Wait till CMD DONE status */ 84 reg = 0; 85 while (!reg) { 86 reg = readl(priv->spmi_core + SPMI_CH_OFFSET(channel) + 87 SPMI_REG_STATUS); 88 } 89 90 if (reg ^ SPMI_STATUS_DONE) { 91 printf("SPMI write failure.\n"); 92 return -EIO; 93 } 94 95 return 0; 96 } 97 98 static int msm_spmi_read(struct udevice *dev, int usid, int pid, int off) 99 { 100 struct msm_spmi_priv *priv = dev_get_priv(dev); 101 unsigned channel; 102 uint32_t reg = 0; 103 104 if (usid >= SPMI_MAX_SLAVES) 105 return -EIO; 106 if (pid >= SPMI_MAX_PERIPH) 107 return -EIO; 108 109 channel = priv->channel_map[usid][pid]; 110 111 /* Disable IRQ mode for the current channel*/ 112 writel(0x0, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CONFIG); 113 114 /* Prepare read command */ 115 reg |= SPMI_CMD_EXT_REG_READ_LONG << SPMI_CMD_OPCODE_SHIFT; 116 reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT); 117 reg |= (pid << SPMI_CMD_ADDR_SHIFT); 118 reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT); 119 reg |= 1; /* byte count */ 120 121 /* Request read */ 122 writel(reg, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0); 123 124 /* Wait till CMD DONE status */ 125 reg = 0; 126 while (!reg) { 127 reg = readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) + 128 SPMI_REG_STATUS); 129 } 130 131 if (reg ^ SPMI_STATUS_DONE) { 132 printf("SPMI read failure.\n"); 133 return -EIO; 134 } 135 136 /* Read the data */ 137 return readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) + 138 SPMI_REG_RDATA) & 0xFF; 139 } 140 141 static struct dm_spmi_ops msm_spmi_ops = { 142 .read = msm_spmi_read, 143 .write = msm_spmi_write, 144 }; 145 146 static int msm_spmi_probe(struct udevice *dev) 147 { 148 struct udevice *parent = dev->parent; 149 struct msm_spmi_priv *priv = dev_get_priv(dev); 150 int i; 151 152 priv->arb_chnl = dev_get_addr(dev); 153 priv->spmi_core = fdtdec_get_addr_size_auto_parent(gd->fdt_blob, 154 parent->of_offset, 155 dev->of_offset, 156 "reg", 1, NULL, 157 false); 158 priv->spmi_obs = fdtdec_get_addr_size_auto_parent(gd->fdt_blob, 159 parent->of_offset, 160 dev->of_offset, "reg", 161 2, NULL, false); 162 if (priv->arb_chnl == FDT_ADDR_T_NONE || 163 priv->spmi_core == FDT_ADDR_T_NONE || 164 priv->spmi_obs == FDT_ADDR_T_NONE) 165 return -EINVAL; 166 167 /* Scan peripherals connected to each SPMI channel */ 168 for (i = 0; i < SPMI_MAX_CHANNELS ; i++) { 169 uint32_t periph = readl(priv->arb_chnl + ARB_CHANNEL_OFFSET(i)); 170 uint8_t slave_id = (periph & 0xf0000) >> 16; 171 uint8_t pid = (periph & 0xff00) >> 8; 172 173 priv->channel_map[slave_id][pid] = i; 174 } 175 return 0; 176 } 177 178 static const struct udevice_id msm_spmi_ids[] = { 179 { .compatible = "qcom,spmi-pmic-arb" }, 180 { } 181 }; 182 183 U_BOOT_DRIVER(msm_spmi) = { 184 .name = "msm_spmi", 185 .id = UCLASS_SPMI, 186 .of_match = msm_spmi_ids, 187 .ops = &msm_spmi_ops, 188 .probe = msm_spmi_probe, 189 .priv_auto_alloc_size = sizeof(struct msm_spmi_priv), 190 }; 191