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