1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) Maxime Coquelin 2015 4 * Copyright (C) STMicroelectronics SA 2017 5 * Authors: Maxime Coquelin <mcoquelin.stm32@gmail.com> 6 * Gerald Baeza <gerald_baeza@yahoo.fr> 7 */ 8 9 #define DRIVER_NAME "stm32-usart" 10 11 struct stm32_usart_offsets { 12 u8 cr1; 13 u8 cr2; 14 u8 cr3; 15 u8 brr; 16 u8 gtpr; 17 u8 rtor; 18 u8 rqr; 19 u8 isr; 20 u8 icr; 21 u8 rdr; 22 u8 tdr; 23 }; 24 25 struct stm32_usart_config { 26 u8 uart_enable_bit; /* USART_CR1_UE */ 27 bool has_7bits_data; 28 bool has_swap; 29 bool has_wakeup; 30 bool has_fifo; 31 int fifosize; 32 }; 33 34 struct stm32_usart_info { 35 struct stm32_usart_offsets ofs; 36 struct stm32_usart_config cfg; 37 }; 38 39 #define UNDEF_REG 0xff 40 41 /* Register offsets */ 42 struct stm32_usart_info stm32f4_info = { 43 .ofs = { 44 .isr = 0x00, 45 .rdr = 0x04, 46 .tdr = 0x04, 47 .brr = 0x08, 48 .cr1 = 0x0c, 49 .cr2 = 0x10, 50 .cr3 = 0x14, 51 .gtpr = 0x18, 52 .rtor = UNDEF_REG, 53 .rqr = UNDEF_REG, 54 .icr = UNDEF_REG, 55 }, 56 .cfg = { 57 .uart_enable_bit = 13, 58 .has_7bits_data = false, 59 .fifosize = 1, 60 } 61 }; 62 63 struct stm32_usart_info stm32f7_info = { 64 .ofs = { 65 .cr1 = 0x00, 66 .cr2 = 0x04, 67 .cr3 = 0x08, 68 .brr = 0x0c, 69 .gtpr = 0x10, 70 .rtor = 0x14, 71 .rqr = 0x18, 72 .isr = 0x1c, 73 .icr = 0x20, 74 .rdr = 0x24, 75 .tdr = 0x28, 76 }, 77 .cfg = { 78 .uart_enable_bit = 0, 79 .has_7bits_data = true, 80 .has_swap = true, 81 .fifosize = 1, 82 } 83 }; 84 85 struct stm32_usart_info stm32h7_info = { 86 .ofs = { 87 .cr1 = 0x00, 88 .cr2 = 0x04, 89 .cr3 = 0x08, 90 .brr = 0x0c, 91 .gtpr = 0x10, 92 .rtor = 0x14, 93 .rqr = 0x18, 94 .isr = 0x1c, 95 .icr = 0x20, 96 .rdr = 0x24, 97 .tdr = 0x28, 98 }, 99 .cfg = { 100 .uart_enable_bit = 0, 101 .has_7bits_data = true, 102 .has_swap = true, 103 .has_wakeup = true, 104 .has_fifo = true, 105 .fifosize = 16, 106 } 107 }; 108 109 /* USART_SR (F4) / USART_ISR (F7) */ 110 #define USART_SR_PE BIT(0) 111 #define USART_SR_FE BIT(1) 112 #define USART_SR_NE BIT(2) /* F7 (NF for F4) */ 113 #define USART_SR_ORE BIT(3) 114 #define USART_SR_IDLE BIT(4) 115 #define USART_SR_RXNE BIT(5) 116 #define USART_SR_TC BIT(6) 117 #define USART_SR_TXE BIT(7) 118 #define USART_SR_CTSIF BIT(9) 119 #define USART_SR_CTS BIT(10) /* F7 */ 120 #define USART_SR_RTOF BIT(11) /* F7 */ 121 #define USART_SR_EOBF BIT(12) /* F7 */ 122 #define USART_SR_ABRE BIT(14) /* F7 */ 123 #define USART_SR_ABRF BIT(15) /* F7 */ 124 #define USART_SR_BUSY BIT(16) /* F7 */ 125 #define USART_SR_CMF BIT(17) /* F7 */ 126 #define USART_SR_SBKF BIT(18) /* F7 */ 127 #define USART_SR_WUF BIT(20) /* H7 */ 128 #define USART_SR_TEACK BIT(21) /* F7 */ 129 #define USART_SR_ERR_MASK (USART_SR_ORE | USART_SR_NE | USART_SR_FE |\ 130 USART_SR_PE) 131 /* Dummy bits */ 132 #define USART_SR_DUMMY_RX BIT(16) 133 134 /* USART_DR */ 135 #define USART_DR_MASK GENMASK(8, 0) 136 137 /* USART_BRR */ 138 #define USART_BRR_DIV_F_MASK GENMASK(3, 0) 139 #define USART_BRR_DIV_M_MASK GENMASK(15, 4) 140 #define USART_BRR_DIV_M_SHIFT 4 141 #define USART_BRR_04_R_SHIFT 1 142 143 /* USART_CR1 */ 144 #define USART_CR1_SBK BIT(0) 145 #define USART_CR1_RWU BIT(1) /* F4 */ 146 #define USART_CR1_UESM BIT(1) /* H7 */ 147 #define USART_CR1_RE BIT(2) 148 #define USART_CR1_TE BIT(3) 149 #define USART_CR1_IDLEIE BIT(4) 150 #define USART_CR1_RXNEIE BIT(5) 151 #define USART_CR1_TCIE BIT(6) 152 #define USART_CR1_TXEIE BIT(7) 153 #define USART_CR1_PEIE BIT(8) 154 #define USART_CR1_PS BIT(9) 155 #define USART_CR1_PCE BIT(10) 156 #define USART_CR1_WAKE BIT(11) 157 #define USART_CR1_M0 BIT(12) /* F7 (CR1_M for F4) */ 158 #define USART_CR1_MME BIT(13) /* F7 */ 159 #define USART_CR1_CMIE BIT(14) /* F7 */ 160 #define USART_CR1_OVER8 BIT(15) 161 #define USART_CR1_DEDT_MASK GENMASK(20, 16) /* F7 */ 162 #define USART_CR1_DEAT_MASK GENMASK(25, 21) /* F7 */ 163 #define USART_CR1_RTOIE BIT(26) /* F7 */ 164 #define USART_CR1_EOBIE BIT(27) /* F7 */ 165 #define USART_CR1_M1 BIT(28) /* F7 */ 166 #define USART_CR1_IE_MASK (GENMASK(8, 4) | BIT(14) | BIT(26) | BIT(27)) 167 #define USART_CR1_FIFOEN BIT(29) /* H7 */ 168 #define USART_CR1_DEAT_SHIFT 21 169 #define USART_CR1_DEDT_SHIFT 16 170 171 /* USART_CR2 */ 172 #define USART_CR2_ADD_MASK GENMASK(3, 0) /* F4 */ 173 #define USART_CR2_ADDM7 BIT(4) /* F7 */ 174 #define USART_CR2_LBCL BIT(8) 175 #define USART_CR2_CPHA BIT(9) 176 #define USART_CR2_CPOL BIT(10) 177 #define USART_CR2_CLKEN BIT(11) 178 #define USART_CR2_STOP_2B BIT(13) 179 #define USART_CR2_STOP_MASK GENMASK(13, 12) 180 #define USART_CR2_LINEN BIT(14) 181 #define USART_CR2_SWAP BIT(15) /* F7 */ 182 #define USART_CR2_RXINV BIT(16) /* F7 */ 183 #define USART_CR2_TXINV BIT(17) /* F7 */ 184 #define USART_CR2_DATAINV BIT(18) /* F7 */ 185 #define USART_CR2_MSBFIRST BIT(19) /* F7 */ 186 #define USART_CR2_ABREN BIT(20) /* F7 */ 187 #define USART_CR2_ABRMOD_MASK GENMASK(22, 21) /* F7 */ 188 #define USART_CR2_RTOEN BIT(23) /* F7 */ 189 #define USART_CR2_ADD_F7_MASK GENMASK(31, 24) /* F7 */ 190 191 /* USART_CR3 */ 192 #define USART_CR3_EIE BIT(0) 193 #define USART_CR3_IREN BIT(1) 194 #define USART_CR3_IRLP BIT(2) 195 #define USART_CR3_HDSEL BIT(3) 196 #define USART_CR3_NACK BIT(4) 197 #define USART_CR3_SCEN BIT(5) 198 #define USART_CR3_DMAR BIT(6) 199 #define USART_CR3_DMAT BIT(7) 200 #define USART_CR3_RTSE BIT(8) 201 #define USART_CR3_CTSE BIT(9) 202 #define USART_CR3_CTSIE BIT(10) 203 #define USART_CR3_ONEBIT BIT(11) 204 #define USART_CR3_OVRDIS BIT(12) /* F7 */ 205 #define USART_CR3_DDRE BIT(13) /* F7 */ 206 #define USART_CR3_DEM BIT(14) /* F7 */ 207 #define USART_CR3_DEP BIT(15) /* F7 */ 208 #define USART_CR3_SCARCNT_MASK GENMASK(19, 17) /* F7 */ 209 #define USART_CR3_WUS_MASK GENMASK(21, 20) /* H7 */ 210 #define USART_CR3_WUS_START_BIT BIT(21) /* H7 */ 211 #define USART_CR3_WUFIE BIT(22) /* H7 */ 212 #define USART_CR3_TXFTIE BIT(23) /* H7 */ 213 #define USART_CR3_TCBGTIE BIT(24) /* H7 */ 214 #define USART_CR3_RXFTCFG_MASK GENMASK(27, 25) /* H7 */ 215 #define USART_CR3_RXFTCFG_SHIFT 25 /* H7 */ 216 #define USART_CR3_RXFTIE BIT(28) /* H7 */ 217 #define USART_CR3_TXFTCFG_MASK GENMASK(31, 29) /* H7 */ 218 #define USART_CR3_TXFTCFG_SHIFT 29 /* H7 */ 219 220 /* USART_GTPR */ 221 #define USART_GTPR_PSC_MASK GENMASK(7, 0) 222 #define USART_GTPR_GT_MASK GENMASK(15, 8) 223 224 /* USART_RTOR */ 225 #define USART_RTOR_RTO_MASK GENMASK(23, 0) /* F7 */ 226 #define USART_RTOR_BLEN_MASK GENMASK(31, 24) /* F7 */ 227 228 /* USART_RQR */ 229 #define USART_RQR_ABRRQ BIT(0) /* F7 */ 230 #define USART_RQR_SBKRQ BIT(1) /* F7 */ 231 #define USART_RQR_MMRQ BIT(2) /* F7 */ 232 #define USART_RQR_RXFRQ BIT(3) /* F7 */ 233 #define USART_RQR_TXFRQ BIT(4) /* F7 */ 234 235 /* USART_ICR */ 236 #define USART_ICR_PECF BIT(0) /* F7 */ 237 #define USART_ICR_FECF BIT(1) /* F7 */ 238 #define USART_ICR_ORECF BIT(3) /* F7 */ 239 #define USART_ICR_IDLECF BIT(4) /* F7 */ 240 #define USART_ICR_TCCF BIT(6) /* F7 */ 241 #define USART_ICR_CTSCF BIT(9) /* F7 */ 242 #define USART_ICR_RTOCF BIT(11) /* F7 */ 243 #define USART_ICR_EOBCF BIT(12) /* F7 */ 244 #define USART_ICR_CMCF BIT(17) /* F7 */ 245 #define USART_ICR_WUCF BIT(20) /* H7 */ 246 247 #define STM32_SERIAL_NAME "ttySTM" 248 #define STM32_MAX_PORTS 8 249 250 #define RX_BUF_L 4096 /* dma rx buffer length */ 251 #define RX_BUF_P (RX_BUF_L / 2) /* dma rx buffer period */ 252 #define TX_BUF_L RX_BUF_L /* dma tx buffer length */ 253 254 #define STM32_USART_TIMEOUT_USEC USEC_PER_SEC /* 1s timeout in µs */ 255 256 struct stm32_port { 257 struct uart_port port; 258 struct clk *clk; 259 const struct stm32_usart_info *info; 260 struct dma_chan *rx_ch; /* dma rx channel */ 261 dma_addr_t rx_dma_buf; /* dma rx buffer bus address */ 262 unsigned char *rx_buf; /* dma rx buffer cpu address */ 263 struct dma_chan *tx_ch; /* dma tx channel */ 264 dma_addr_t tx_dma_buf; /* dma tx buffer bus address */ 265 unsigned char *tx_buf; /* dma tx buffer cpu address */ 266 u32 cr1_irq; /* USART_CR1_RXNEIE or RTOIE */ 267 u32 cr3_irq; /* USART_CR3_RXFTIE */ 268 int last_res; 269 bool tx_dma_busy; /* dma tx transaction in progress */ 270 bool throttled; /* port throttled */ 271 bool hw_flow_control; 272 bool swap; /* swap RX & TX pins */ 273 bool fifoen; 274 bool txdone; 275 int rxftcfg; /* RX FIFO threshold CFG */ 276 int txftcfg; /* TX FIFO threshold CFG */ 277 bool wakeup_src; 278 int rdr_mask; /* receive data register mask */ 279 struct mctrl_gpios *gpios; /* modem control gpios */ 280 struct dma_tx_state rx_dma_state; 281 }; 282 283 static struct stm32_port stm32_ports[STM32_MAX_PORTS]; 284 static struct uart_driver stm32_usart_driver; 285