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 u16 cr1; 13 u16 cr2; 14 u16 cr3; 15 u16 brr; 16 u16 gtpr; 17 u16 rtor; 18 u16 rqr; 19 u16 isr; 20 u16 icr; 21 u16 rdr; 22 u16 tdr; 23 u16 presc; 24 u16 hwcfgr1; 25 }; 26 27 struct stm32_usart_config { 28 u8 uart_enable_bit; /* USART_CR1_UE */ 29 bool has_7bits_data; 30 bool has_swap; 31 bool has_wakeup; 32 bool has_fifo; 33 }; 34 35 struct stm32_usart_info { 36 struct stm32_usart_offsets ofs; 37 struct stm32_usart_config cfg; 38 }; 39 40 #define UNDEF_REG 0xffff 41 42 /* USART_SR (F4) / USART_ISR (F7) */ 43 #define USART_SR_PE BIT(0) 44 #define USART_SR_FE BIT(1) 45 #define USART_SR_NE BIT(2) /* F7 (NF for F4) */ 46 #define USART_SR_ORE BIT(3) 47 #define USART_SR_IDLE BIT(4) 48 #define USART_SR_RXNE BIT(5) 49 #define USART_SR_TC BIT(6) 50 #define USART_SR_TXE BIT(7) 51 #define USART_SR_CTSIF BIT(9) 52 #define USART_SR_CTS BIT(10) /* F7 */ 53 #define USART_SR_RTOF BIT(11) /* F7 */ 54 #define USART_SR_EOBF BIT(12) /* F7 */ 55 #define USART_SR_ABRE BIT(14) /* F7 */ 56 #define USART_SR_ABRF BIT(15) /* F7 */ 57 #define USART_SR_BUSY BIT(16) /* F7 */ 58 #define USART_SR_CMF BIT(17) /* F7 */ 59 #define USART_SR_SBKF BIT(18) /* F7 */ 60 #define USART_SR_WUF BIT(20) /* H7 */ 61 #define USART_SR_TEACK BIT(21) /* F7 */ 62 #define USART_SR_ERR_MASK (USART_SR_ORE | USART_SR_NE | USART_SR_FE |\ 63 USART_SR_PE) 64 /* Dummy bits */ 65 #define USART_SR_DUMMY_RX BIT(16) 66 67 /* USART_DR */ 68 #define USART_DR_MASK GENMASK(8, 0) 69 70 /* USART_BRR */ 71 #define USART_BRR_DIV_F_MASK GENMASK(3, 0) 72 #define USART_BRR_DIV_M_MASK GENMASK(15, 4) 73 #define USART_BRR_DIV_M_SHIFT 4 74 #define USART_BRR_04_R_SHIFT 1 75 #define USART_BRR_MASK (USART_BRR_DIV_M_MASK | USART_BRR_DIV_F_MASK) 76 77 /* USART_CR1 */ 78 #define USART_CR1_SBK BIT(0) 79 #define USART_CR1_RWU BIT(1) /* F4 */ 80 #define USART_CR1_UESM BIT(1) /* H7 */ 81 #define USART_CR1_RE BIT(2) 82 #define USART_CR1_TE BIT(3) 83 #define USART_CR1_IDLEIE BIT(4) 84 #define USART_CR1_RXNEIE BIT(5) 85 #define USART_CR1_TCIE BIT(6) 86 #define USART_CR1_TXEIE BIT(7) 87 #define USART_CR1_PEIE BIT(8) 88 #define USART_CR1_PS BIT(9) 89 #define USART_CR1_PCE BIT(10) 90 #define USART_CR1_WAKE BIT(11) 91 #define USART_CR1_M0 BIT(12) /* F7 (CR1_M for F4) */ 92 #define USART_CR1_MME BIT(13) /* F7 */ 93 #define USART_CR1_CMIE BIT(14) /* F7 */ 94 #define USART_CR1_OVER8 BIT(15) 95 #define USART_CR1_DEDT_MASK GENMASK(20, 16) /* F7 */ 96 #define USART_CR1_DEAT_MASK GENMASK(25, 21) /* F7 */ 97 #define USART_CR1_RTOIE BIT(26) /* F7 */ 98 #define USART_CR1_EOBIE BIT(27) /* F7 */ 99 #define USART_CR1_M1 BIT(28) /* F7 */ 100 #define USART_CR1_IE_MASK (GENMASK(8, 4) | BIT(14) | BIT(26) | BIT(27)) 101 #define USART_CR1_FIFOEN BIT(29) /* H7 */ 102 #define USART_CR1_DEAT_SHIFT 21 103 #define USART_CR1_DEDT_SHIFT 16 104 105 /* USART_CR2 */ 106 #define USART_CR2_ADD_MASK GENMASK(3, 0) /* F4 */ 107 #define USART_CR2_ADDM7 BIT(4) /* F7 */ 108 #define USART_CR2_LBCL BIT(8) 109 #define USART_CR2_CPHA BIT(9) 110 #define USART_CR2_CPOL BIT(10) 111 #define USART_CR2_CLKEN BIT(11) 112 #define USART_CR2_STOP_2B BIT(13) 113 #define USART_CR2_STOP_MASK GENMASK(13, 12) 114 #define USART_CR2_LINEN BIT(14) 115 #define USART_CR2_SWAP BIT(15) /* F7 */ 116 #define USART_CR2_RXINV BIT(16) /* F7 */ 117 #define USART_CR2_TXINV BIT(17) /* F7 */ 118 #define USART_CR2_DATAINV BIT(18) /* F7 */ 119 #define USART_CR2_MSBFIRST BIT(19) /* F7 */ 120 #define USART_CR2_ABREN BIT(20) /* F7 */ 121 #define USART_CR2_ABRMOD_MASK GENMASK(22, 21) /* F7 */ 122 #define USART_CR2_RTOEN BIT(23) /* F7 */ 123 #define USART_CR2_ADD_F7_MASK GENMASK(31, 24) /* F7 */ 124 125 /* USART_CR3 */ 126 #define USART_CR3_EIE BIT(0) 127 #define USART_CR3_IREN BIT(1) 128 #define USART_CR3_IRLP BIT(2) 129 #define USART_CR3_HDSEL BIT(3) 130 #define USART_CR3_NACK BIT(4) 131 #define USART_CR3_SCEN BIT(5) 132 #define USART_CR3_DMAR BIT(6) 133 #define USART_CR3_DMAT BIT(7) 134 #define USART_CR3_RTSE BIT(8) 135 #define USART_CR3_CTSE BIT(9) 136 #define USART_CR3_CTSIE BIT(10) 137 #define USART_CR3_ONEBIT BIT(11) 138 #define USART_CR3_OVRDIS BIT(12) /* F7 */ 139 #define USART_CR3_DDRE BIT(13) /* F7 */ 140 #define USART_CR3_DEM BIT(14) /* F7 */ 141 #define USART_CR3_DEP BIT(15) /* F7 */ 142 #define USART_CR3_SCARCNT_MASK GENMASK(19, 17) /* F7 */ 143 #define USART_CR3_WUS_MASK GENMASK(21, 20) /* H7 */ 144 #define USART_CR3_WUS_START_BIT BIT(21) /* H7 */ 145 #define USART_CR3_WUFIE BIT(22) /* H7 */ 146 #define USART_CR3_TXFTIE BIT(23) /* H7 */ 147 #define USART_CR3_TCBGTIE BIT(24) /* H7 */ 148 #define USART_CR3_RXFTCFG_MASK GENMASK(27, 25) /* H7 */ 149 #define USART_CR3_RXFTCFG_SHIFT 25 /* H7 */ 150 #define USART_CR3_RXFTIE BIT(28) /* H7 */ 151 #define USART_CR3_TXFTCFG_MASK GENMASK(31, 29) /* H7 */ 152 #define USART_CR3_TXFTCFG_SHIFT 29 /* H7 */ 153 154 /* USART_GTPR */ 155 #define USART_GTPR_PSC_MASK GENMASK(7, 0) 156 #define USART_GTPR_GT_MASK GENMASK(15, 8) 157 158 /* USART_RTOR */ 159 #define USART_RTOR_RTO_MASK GENMASK(23, 0) /* F7 */ 160 #define USART_RTOR_BLEN_MASK GENMASK(31, 24) /* F7 */ 161 162 /* USART_RQR */ 163 #define USART_RQR_ABRRQ BIT(0) /* F7 */ 164 #define USART_RQR_SBKRQ BIT(1) /* F7 */ 165 #define USART_RQR_MMRQ BIT(2) /* F7 */ 166 #define USART_RQR_RXFRQ BIT(3) /* F7 */ 167 #define USART_RQR_TXFRQ BIT(4) /* F7 */ 168 169 /* USART_ICR */ 170 #define USART_ICR_PECF BIT(0) /* F7 */ 171 #define USART_ICR_FECF BIT(1) /* F7 */ 172 #define USART_ICR_ORECF BIT(3) /* F7 */ 173 #define USART_ICR_IDLECF BIT(4) /* F7 */ 174 #define USART_ICR_TCCF BIT(6) /* F7 */ 175 #define USART_ICR_CTSCF BIT(9) /* F7 */ 176 #define USART_ICR_RTOCF BIT(11) /* F7 */ 177 #define USART_ICR_EOBCF BIT(12) /* F7 */ 178 #define USART_ICR_CMCF BIT(17) /* F7 */ 179 #define USART_ICR_WUCF BIT(20) /* H7 */ 180 181 /* USART_PRESC */ 182 #define USART_PRESC GENMASK(3, 0) /* H7 */ 183 #define USART_PRESC_MAX 0b1011 184 185 /* USART_HWCFCR1 */ 186 #define USART_HWCFGR1_CFG8 GENMASK(31, 28) /* MP1 */ 187 188 #define STM32_SERIAL_NAME "ttySTM" 189 #define STM32_MAX_PORTS 9 190 #define STM32H7_USART_FIFO_SIZE 16 191 192 #define RX_BUF_L 4096 /* dma rx buffer length */ 193 #define RX_BUF_P (RX_BUF_L / 2) /* dma rx buffer period */ 194 #define TX_BUF_L RX_BUF_L /* dma tx buffer length */ 195 196 #define STM32_USART_TIMEOUT_USEC USEC_PER_SEC /* 1s timeout in µs */ 197 198 struct stm32_port { 199 struct uart_port port; 200 struct clk *clk; 201 const struct stm32_usart_info *info; 202 struct dma_chan *rx_ch; /* dma rx channel */ 203 dma_addr_t rx_dma_buf; /* dma rx buffer bus address */ 204 unsigned char *rx_buf; /* dma rx buffer cpu address */ 205 struct dma_chan *tx_ch; /* dma tx channel */ 206 dma_addr_t tx_dma_buf; /* dma tx buffer bus address */ 207 unsigned char *tx_buf; /* dma tx buffer cpu address */ 208 u32 cr1_irq; /* USART_CR1_RXNEIE or RTOIE */ 209 u32 cr3_irq; /* USART_CR3_RXFTIE */ 210 int last_res; 211 bool tx_dma_busy; /* dma tx transaction in progress */ 212 bool rx_dma_busy; /* dma rx transaction in progress */ 213 bool throttled; /* port throttled */ 214 bool hw_flow_control; 215 bool swap; /* swap RX & TX pins */ 216 bool fifoen; 217 int rxftcfg; /* RX FIFO threshold CFG */ 218 int txftcfg; /* TX FIFO threshold CFG */ 219 bool wakeup_src; 220 int rdr_mask; /* receive data register mask */ 221 struct mctrl_gpios *gpios; /* modem control gpios */ 222 struct dma_tx_state rx_dma_state; 223 }; 224 225 static struct stm32_port stm32_ports[STM32_MAX_PORTS]; 226 static struct uart_driver stm32_usart_driver; 227