drivers/tty/serial/stm32-usart.h

   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_wakeup;
  29         bool has_fifo;
  30         int fifosize;
  31 };
  32
  33 struct stm32_usart_info {
  34         struct stm32_usart_offsets ofs;
  35         struct stm32_usart_config cfg;
  36 };
  37
  38 #define UNDEF_REG 0xff
  39
  40 /* Register offsets */
  41 struct stm32_usart_info stm32f4_info = {
  42         .ofs = {
  43                 .isr    = 0x00,
  44                 .rdr    = 0x04,
  45                 .tdr    = 0x04,
  46                 .brr    = 0x08,
  47                 .cr1    = 0x0c,
  48                 .cr2    = 0x10,
  49                 .cr3    = 0x14,
  50                 .gtpr   = 0x18,
  51                 .rtor   = UNDEF_REG,
  52                 .rqr    = UNDEF_REG,
  53                 .icr    = UNDEF_REG,
  54         },
  55         .cfg = {
  56                 .uart_enable_bit = 13,
  57                 .has_7bits_data = false,
  58                 .fifosize = 1,
  59         }
  60 };
  61
  62 struct stm32_usart_info stm32f7_info = {
  63         .ofs = {
  64                 .cr1    = 0x00,
  65                 .cr2    = 0x04,
  66                 .cr3    = 0x08,
  67                 .brr    = 0x0c,
  68                 .gtpr   = 0x10,
  69                 .rtor   = 0x14,
  70                 .rqr    = 0x18,
  71                 .isr    = 0x1c,
  72                 .icr    = 0x20,
  73                 .rdr    = 0x24,
  74                 .tdr    = 0x28,
  75         },
  76         .cfg = {
  77                 .uart_enable_bit = 0,
  78                 .has_7bits_data = true,
  79                 .fifosize = 1,
  80         }
  81 };
  82
  83 struct stm32_usart_info stm32h7_info = {
  84         .ofs = {
  85                 .cr1    = 0x00,
  86                 .cr2    = 0x04,
  87                 .cr3    = 0x08,
  88                 .brr    = 0x0c,
  89                 .gtpr   = 0x10,
  90                 .rtor   = 0x14,
  91                 .rqr    = 0x18,
  92                 .isr    = 0x1c,
  93                 .icr    = 0x20,
  94                 .rdr    = 0x24,
  95                 .tdr    = 0x28,
  96         },
  97         .cfg = {
  98                 .uart_enable_bit = 0,
  99                 .has_7bits_data = true,
 100                 .has_wakeup = true,
 101                 .has_fifo = true,
 102                 .fifosize = 16,
 103         }
 104 };
 105
 106 /* USART_SR (F4) / USART_ISR (F7) */
 107 #define USART_SR_PE             BIT(0)
 108 #define USART_SR_FE             BIT(1)
 109 #define USART_SR_NF             BIT(2)
 110 #define USART_SR_ORE            BIT(3)
 111 #define USART_SR_IDLE           BIT(4)
 112 #define USART_SR_RXNE           BIT(5)
 113 #define USART_SR_TC             BIT(6)
 114 #define USART_SR_TXE            BIT(7)
 115 #define USART_SR_CTSIF          BIT(9)
 116 #define USART_SR_CTS            BIT(10)         /* F7 */
 117 #define USART_SR_RTOF           BIT(11)         /* F7 */
 118 #define USART_SR_EOBF           BIT(12)         /* F7 */
 119 #define USART_SR_ABRE           BIT(14)         /* F7 */
 120 #define USART_SR_ABRF           BIT(15)         /* F7 */
 121 #define USART_SR_BUSY           BIT(16)         /* F7 */
 122 #define USART_SR_CMF            BIT(17)         /* F7 */
 123 #define USART_SR_SBKF           BIT(18)         /* F7 */
 124 #define USART_SR_WUF            BIT(20)         /* H7 */
 125 #define USART_SR_TEACK          BIT(21)         /* F7 */
 126 #define USART_SR_ERR_MASK       (USART_SR_ORE | USART_SR_FE | USART_SR_PE)
 127 /* Dummy bits */
 128 #define USART_SR_DUMMY_RX       BIT(16)
 129
 130 /* USART_ICR (F7) */
 131 #define USART_CR_TC             BIT(6)
 132
 133 /* USART_DR */
 134 #define USART_DR_MASK           GENMASK(8, 0)
 135
 136 /* USART_BRR */
 137 #define USART_BRR_DIV_F_MASK    GENMASK(3, 0)
 138 #define USART_BRR_DIV_M_MASK    GENMASK(15, 4)
 139 #define USART_BRR_DIV_M_SHIFT   4
 140 #define USART_BRR_04_R_SHIFT    1
 141
 142 /* USART_CR1 */
 143 #define USART_CR1_SBK           BIT(0)
 144 #define USART_CR1_RWU           BIT(1)          /* F4 */
 145 #define USART_CR1_UESM          BIT(1)          /* H7 */
 146 #define USART_CR1_RE            BIT(2)
 147 #define USART_CR1_TE            BIT(3)
 148 #define USART_CR1_IDLEIE        BIT(4)
 149 #define USART_CR1_RXNEIE        BIT(5)
 150 #define USART_CR1_TCIE          BIT(6)
 151 #define USART_CR1_TXEIE         BIT(7)
 152 #define USART_CR1_PEIE          BIT(8)
 153 #define USART_CR1_PS            BIT(9)
 154 #define USART_CR1_PCE           BIT(10)
 155 #define USART_CR1_WAKE          BIT(11)
 156 #define USART_CR1_M0            BIT(12)         /* F7 (CR1_M for F4) */
 157 #define USART_CR1_MME           BIT(13)         /* F7 */
 158 #define USART_CR1_CMIE          BIT(14)         /* F7 */
 159 #define USART_CR1_OVER8         BIT(15)
 160 #define USART_CR1_DEDT_MASK     GENMASK(20, 16) /* F7 */
 161 #define USART_CR1_DEAT_MASK     GENMASK(25, 21) /* F7 */
 162 #define USART_CR1_RTOIE         BIT(26)         /* F7 */
 163 #define USART_CR1_EOBIE         BIT(27)         /* F7 */
 164 #define USART_CR1_M1            BIT(28)         /* F7 */
 165 #define USART_CR1_IE_MASK       (GENMASK(8, 4) | BIT(14) | BIT(26) | BIT(27))
 166 #define USART_CR1_FIFOEN        BIT(29)         /* H7 */
 167 #define USART_CR1_DEAT_SHIFT 21
 168 #define USART_CR1_DEDT_SHIFT 16
 169
 170 /* USART_CR2 */
 171 #define USART_CR2_ADD_MASK      GENMASK(3, 0)   /* F4 */
 172 #define USART_CR2_ADDM7         BIT(4)          /* F7 */
 173 #define USART_CR2_LBCL          BIT(8)
 174 #define USART_CR2_CPHA          BIT(9)
 175 #define USART_CR2_CPOL          BIT(10)
 176 #define USART_CR2_CLKEN         BIT(11)
 177 #define USART_CR2_STOP_2B       BIT(13)
 178 #define USART_CR2_STOP_MASK     GENMASK(13, 12)
 179 #define USART_CR2_LINEN         BIT(14)
 180 #define USART_CR2_SWAP          BIT(15)         /* F7 */
 181 #define USART_CR2_RXINV         BIT(16)         /* F7 */
 182 #define USART_CR2_TXINV         BIT(17)         /* F7 */
 183 #define USART_CR2_DATAINV       BIT(18)         /* F7 */
 184 #define USART_CR2_MSBFIRST      BIT(19)         /* F7 */
 185 #define USART_CR2_ABREN         BIT(20)         /* F7 */
 186 #define USART_CR2_ABRMOD_MASK   GENMASK(22, 21) /* F7 */
 187 #define USART_CR2_RTOEN         BIT(23)         /* F7 */
 188 #define USART_CR2_ADD_F7_MASK   GENMASK(31, 24) /* F7 */
 189
 190 /* USART_CR3 */
 191 #define USART_CR3_EIE           BIT(0)
 192 #define USART_CR3_IREN          BIT(1)
 193 #define USART_CR3_IRLP          BIT(2)
 194 #define USART_CR3_HDSEL         BIT(3)
 195 #define USART_CR3_NACK          BIT(4)
 196 #define USART_CR3_SCEN          BIT(5)
 197 #define USART_CR3_DMAR          BIT(6)
 198 #define USART_CR3_DMAT          BIT(7)
 199 #define USART_CR3_RTSE          BIT(8)
 200 #define USART_CR3_CTSE          BIT(9)
 201 #define USART_CR3_CTSIE         BIT(10)
 202 #define USART_CR3_ONEBIT        BIT(11)
 203 #define USART_CR3_OVRDIS        BIT(12)         /* F7 */
 204 #define USART_CR3_DDRE          BIT(13)         /* F7 */
 205 #define USART_CR3_DEM           BIT(14)         /* F7 */
 206 #define USART_CR3_DEP           BIT(15)         /* F7 */
 207 #define USART_CR3_SCARCNT_MASK  GENMASK(19, 17) /* F7 */
 208 #define USART_CR3_WUS_MASK      GENMASK(21, 20) /* H7 */
 209 #define USART_CR3_WUS_START_BIT BIT(21)         /* H7 */
 210 #define USART_CR3_WUFIE         BIT(22)         /* H7 */
 211 #define USART_CR3_TXFTIE        BIT(23)         /* H7 */
 212 #define USART_CR3_TCBGTIE       BIT(24)         /* H7 */
 213 #define USART_CR3_RXFTCFG_MASK  GENMASK(27, 25) /* H7 */
 214 #define USART_CR3_RXFTCFG_SHIFT 25              /* H7 */
 215 #define USART_CR3_RXFTIE        BIT(28)         /* H7 */
 216 #define USART_CR3_TXFTCFG_MASK  GENMASK(31, 29) /* H7 */
 217 #define USART_CR3_TXFTCFG_SHIFT 29              /* H7 */
 218
 219 /* TX FIFO threashold set to half of its depth */
 220 #define USART_CR3_TXFTCFG_HALF  0x2
 221
 222 /* RX FIFO threashold set to half of its depth */
 223 #define USART_CR3_RXFTCFG_HALF  0x2
 224
 225 /* USART_GTPR */
 226 #define USART_GTPR_PSC_MASK     GENMASK(7, 0)
 227 #define USART_GTPR_GT_MASK      GENMASK(15, 8)
 228
 229 /* USART_RTOR */
 230 #define USART_RTOR_RTO_MASK     GENMASK(23, 0)  /* F7 */
 231 #define USART_RTOR_BLEN_MASK    GENMASK(31, 24) /* F7 */
 232
 233 /* USART_RQR */
 234 #define USART_RQR_ABRRQ         BIT(0)          /* F7 */
 235 #define USART_RQR_SBKRQ         BIT(1)          /* F7 */
 236 #define USART_RQR_MMRQ          BIT(2)          /* F7 */
 237 #define USART_RQR_RXFRQ         BIT(3)          /* F7 */
 238 #define USART_RQR_TXFRQ         BIT(4)          /* F7 */
 239
 240 /* USART_ICR */
 241 #define USART_ICR_PECF          BIT(0)          /* F7 */
 242 #define USART_ICR_FECF          BIT(1)          /* F7 */
 243 #define USART_ICR_ORECF         BIT(3)          /* F7 */
 244 #define USART_ICR_IDLECF        BIT(4)          /* F7 */
 245 #define USART_ICR_TCCF          BIT(6)          /* F7 */
 246 #define USART_ICR_CTSCF         BIT(9)          /* F7 */
 247 #define USART_ICR_RTOCF         BIT(11)         /* F7 */
 248 #define USART_ICR_EOBCF         BIT(12)         /* F7 */
 249 #define USART_ICR_CMCF          BIT(17)         /* F7 */
 250 #define USART_ICR_WUCF          BIT(20)         /* H7 */
 251
 252 #define STM32_SERIAL_NAME "ttySTM"
 253 #define STM32_MAX_PORTS 8
 254
 255 #define RX_BUF_L 200             /* dma rx buffer length     */
 256 #define RX_BUF_P RX_BUF_L        /* dma rx buffer period     */
 257 #define TX_BUF_L 200             /* dma tx buffer length     */
 258
 259 struct stm32_port {
 260         struct uart_port port;
 261         struct clk *clk;
 262         struct stm32_usart_info *info;
 263         struct dma_chan *rx_ch;  /* dma rx channel            */
 264         dma_addr_t rx_dma_buf;   /* dma rx buffer bus address */
 265         unsigned char *rx_buf;   /* dma rx buffer cpu address */
 266         struct dma_chan *tx_ch;  /* dma tx channel            */
 267         dma_addr_t tx_dma_buf;   /* dma tx buffer bus address */
 268         unsigned char *tx_buf;   /* dma tx buffer cpu address */
 269         u32 cr1_irq;             /* USART_CR1_RXNEIE or RTOIE */
 270         u32 cr3_irq;             /* USART_CR3_RXFTIE */
 271         int last_res;
 272         bool tx_dma_busy;        /* dma tx busy               */
 273         bool hw_flow_control;
 274         bool fifoen;
 275         int wakeirq;
 276         int rdr_mask;           /* receive data register mask */
 277 };
 278
 279 static struct stm32_port stm32_ports[STM32_MAX_PORTS];
 280 static struct uart_driver stm32_usart_driver;