/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) Maxime Coquelin 2015
* Copyright (C) STMicroelectronics SA 2017
* Authors: Maxime Coquelin <[email protected]>
* Gerald Baeza <[email protected]>
*/
#define DRIVER_NAME "stm32-usart"
struct stm32_usart_offsets {
u16 cr1;
u16 cr2;
u16 cr3;
u16 brr;
u16 gtpr;
u16 rtor;
u16 rqr;
u16 isr;
u16 icr;
u16 rdr;
u16 tdr;
u16 presc;
u16 hwcfgr1;
};
struct stm32_usart_config {
u8 uart_enable_bit; /* USART_CR1_UE */
bool has_7bits_data;
bool has_swap;
bool has_wakeup;
bool has_fifo;
};
struct stm32_usart_info {
struct stm32_usart_offsets ofs;
struct stm32_usart_config cfg;
};
#define UNDEF_REG 0xffff
/* USART_SR (F4) / USART_ISR (F7) */
#define USART_SR_PE BIT(0)
#define USART_SR_FE BIT(1)
#define USART_SR_NE BIT(2) /* F7 (NF for F4) */
#define USART_SR_ORE BIT(3)
#define USART_SR_IDLE BIT(4)
#define USART_SR_RXNE BIT(5)
#define USART_SR_TC BIT(6)
#define USART_SR_TXE BIT(7)
#define USART_SR_CTSIF BIT(9)
#define USART_SR_CTS BIT(10) /* F7 */
#define USART_SR_RTOF BIT(11) /* F7 */
#define USART_SR_EOBF BIT(12) /* F7 */
#define USART_SR_ABRE BIT(14) /* F7 */
#define USART_SR_ABRF BIT(15) /* F7 */
#define USART_SR_BUSY BIT(16) /* F7 */
#define USART_SR_CMF BIT(17) /* F7 */
#define USART_SR_SBKF BIT(18) /* F7 */
#define USART_SR_WUF BIT(20) /* H7 */
#define USART_SR_TEACK BIT(21) /* F7 */
#define USART_SR_ERR_MASK (USART_SR_ORE | USART_SR_NE | USART_SR_FE |\
USART_SR_PE)
/* Dummy bits */
#define USART_SR_DUMMY_RX BIT(16)
/* USART_DR */
#define USART_DR_MASK GENMASK(8, 0)
/* USART_BRR */
#define USART_BRR_DIV_F_MASK GENMASK(3, 0)
#define USART_BRR_DIV_M_MASK GENMASK(15, 4)
#define USART_BRR_DIV_M_SHIFT 4
#define USART_BRR_04_R_SHIFT 1
#define USART_BRR_MASK (USART_BRR_DIV_M_MASK | USART_BRR_DIV_F_MASK)
/* USART_CR1 */
#define USART_CR1_SBK BIT(0)
#define USART_CR1_RWU BIT(1) /* F4 */
#define USART_CR1_UESM BIT(1) /* H7 */
#define USART_CR1_RE BIT(2)
#define USART_CR1_TE BIT(3)
#define USART_CR1_IDLEIE BIT(4)
#define USART_CR1_RXNEIE BIT(5)
#define USART_CR1_TCIE BIT(6)
#define USART_CR1_TXEIE BIT(7)
#define USART_CR1_PEIE BIT(8)
#define USART_CR1_PS BIT(9)
#define USART_CR1_PCE BIT(10)
#define USART_CR1_WAKE BIT(11)
#define USART_CR1_M0 BIT(12) /* F7 (CR1_M for F4) */
#define USART_CR1_MME BIT(13) /* F7 */
#define USART_CR1_CMIE BIT(14) /* F7 */
#define USART_CR1_OVER8 BIT(15)
#define USART_CR1_DEDT_MASK GENMASK(20, 16) /* F7 */
#define USART_CR1_DEAT_MASK GENMASK(25, 21) /* F7 */
#define USART_CR1_RTOIE BIT(26) /* F7 */
#define USART_CR1_EOBIE BIT(27) /* F7 */
#define USART_CR1_M1 BIT(28) /* F7 */
#define USART_CR1_IE_MASK (GENMASK(8, 4) | BIT(14) | BIT(26) | BIT(27))
#define USART_CR1_FIFOEN BIT(29) /* H7 */
#define USART_CR1_DEAT_SHIFT 21
#define USART_CR1_DEDT_SHIFT 16
/* USART_CR2 */
#define USART_CR2_ADD_MASK GENMASK(3, 0) /* F4 */
#define USART_CR2_ADDM7 BIT(4) /* F7 */
#define USART_CR2_LBCL BIT(8)
#define USART_CR2_CPHA BIT(9)
#define USART_CR2_CPOL BIT(10)
#define USART_CR2_CLKEN BIT(11)
#define USART_CR2_STOP_2B BIT(13)
#define USART_CR2_STOP_MASK GENMASK(13, 12)
#define USART_CR2_LINEN BIT(14)
#define USART_CR2_SWAP BIT(15) /* F7 */
#define USART_CR2_RXINV BIT(16) /* F7 */
#define USART_CR2_TXINV BIT(17) /* F7 */
#define USART_CR2_DATAINV BIT(18) /* F7 */
#define USART_CR2_MSBFIRST BIT(19) /* F7 */
#define USART_CR2_ABREN BIT(20) /* F7 */
#define USART_CR2_ABRMOD_MASK GENMASK(22, 21) /* F7 */
#define USART_CR2_RTOEN BIT(23) /* F7 */
#define USART_CR2_ADD_F7_MASK GENMASK(31, 24) /* F7 */
/* USART_CR3 */
#define USART_CR3_EIE BIT(0)
#define USART_CR3_IREN BIT(1)
#define USART_CR3_IRLP BIT(2)
#define USART_CR3_HDSEL BIT(3)
#define USART_CR3_NACK BIT(4)
#define USART_CR3_SCEN BIT(5)
#define USART_CR3_DMAR BIT(6)
#define USART_CR3_DMAT BIT(7)
#define USART_CR3_RTSE BIT(8)
#define USART_CR3_CTSE BIT(9)
#define USART_CR3_CTSIE BIT(10)
#define USART_CR3_ONEBIT BIT(11)
#define USART_CR3_OVRDIS BIT(12) /* F7 */
#define USART_CR3_DDRE BIT(13) /* F7 */
#define USART_CR3_DEM BIT(14) /* F7 */
#define USART_CR3_DEP BIT(15) /* F7 */
#define USART_CR3_SCARCNT_MASK GENMASK(19, 17) /* F7 */
#define USART_CR3_WUS_MASK GENMASK(21, 20) /* H7 */
#define USART_CR3_WUS_START_BIT BIT(21) /* H7 */
#define USART_CR3_WUFIE BIT(22) /* H7 */
#define USART_CR3_TXFTIE BIT(23) /* H7 */
#define USART_CR3_TCBGTIE BIT(24) /* H7 */
#define USART_CR3_RXFTCFG_MASK GENMASK(27, 25) /* H7 */
#define USART_CR3_RXFTCFG_SHIFT 25 /* H7 */
#define USART_CR3_RXFTIE BIT(28) /* H7 */
#define USART_CR3_TXFTCFG_MASK GENMASK(31, 29) /* H7 */
#define USART_CR3_TXFTCFG_SHIFT 29 /* H7 */
/* USART_GTPR */
#define USART_GTPR_PSC_MASK GENMASK(7, 0)
#define USART_GTPR_GT_MASK GENMASK(15, 8)
/* USART_RTOR */
#define USART_RTOR_RTO_MASK GENMASK(23, 0) /* F7 */
#define USART_RTOR_BLEN_MASK GENMASK(31, 24) /* F7 */
/* USART_RQR */
#define USART_RQR_ABRRQ BIT(0) /* F7 */
#define USART_RQR_SBKRQ BIT(1) /* F7 */
#define USART_RQR_MMRQ BIT(2) /* F7 */
#define USART_RQR_RXFRQ BIT(3) /* F7 */
#define USART_RQR_TXFRQ BIT(4) /* F7 */
/* USART_ICR */
#define USART_ICR_PECF BIT(0) /* F7 */
#define USART_ICR_FECF BIT(1) /* F7 */
#define USART_ICR_ORECF BIT(3) /* F7 */
#define USART_ICR_IDLECF BIT(4) /* F7 */
#define USART_ICR_TCCF BIT(6) /* F7 */
#define USART_ICR_CTSCF BIT(9) /* F7 */
#define USART_ICR_RTOCF BIT(11) /* F7 */
#define USART_ICR_EOBCF BIT(12) /* F7 */
#define USART_ICR_CMCF BIT(17) /* F7 */
#define USART_ICR_WUCF BIT(20) /* H7 */
/* USART_PRESC */
#define USART_PRESC GENMASK(3, 0) /* H7 */
#define USART_PRESC_MAX 0b1011
/* USART_HWCFCR1 */
#define USART_HWCFGR1_CFG8 GENMASK(31, 28) /* MP1 */
#define STM32_SERIAL_NAME "ttySTM"
#define STM32_MAX_PORTS 9
#define STM32H7_USART_FIFO_SIZE 16
#define RX_BUF_L 4096 /* dma rx buffer length */
#define RX_BUF_P (RX_BUF_L / 2) /* dma rx buffer period */
#define TX_BUF_L RX_BUF_L /* dma tx buffer length */
#define STM32_USART_TIMEOUT_USEC USEC_PER_SEC /* 1s timeout in µs */
struct stm32_port {
struct uart_port port;
struct clk *clk;
const struct stm32_usart_info *info;
struct dma_chan *rx_ch; /* dma rx channel */
dma_addr_t rx_dma_buf; /* dma rx buffer bus address */
unsigned char *rx_buf; /* dma rx buffer cpu address */
struct dma_chan *tx_ch; /* dma tx channel */
dma_addr_t tx_dma_buf; /* dma tx buffer bus address */
unsigned char *tx_buf; /* dma tx buffer cpu address */
u32 cr1_irq; /* USART_CR1_RXNEIE or RTOIE */
u32 cr3_irq; /* USART_CR3_RXFTIE */
int last_res;
bool tx_dma_busy; /* dma tx transaction in progress */
bool rx_dma_busy; /* dma rx transaction in progress */
bool throttled; /* port throttled */
bool hw_flow_control;
bool swap; /* swap RX & TX pins */
bool fifoen;
int rxftcfg; /* RX FIFO threshold CFG */
int txftcfg; /* TX FIFO threshold CFG */
bool wakeup_src;
int rdr_mask; /* receive data register mask */
struct mctrl_gpios *gpios; /* modem control gpios */
struct dma_tx_state rx_dma_state;
};
static struct stm32_port stm32_ports[STM32_MAX_PORTS];
static struct uart_driver stm32_usart_driver;
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