diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c index eb4cb480b93e..5644cf2385bb 100644 --- a/drivers/serial/amba-pl011.c +++ b/drivers/serial/amba-pl011.c @@ -69,9 +69,11 @@ struct uart_amba_port { struct uart_port port; struct clk *clk; - unsigned int im; /* interrupt mask */ + unsigned int im; /* interrupt mask */ unsigned int old_status; - unsigned int ifls; /* vendor-specific */ + unsigned int ifls; /* vendor-specific */ + unsigned int lcrh_tx; /* vendor-specific */ + unsigned int lcrh_rx; /* vendor-specific */ bool autorts; }; @@ -79,16 +81,22 @@ struct uart_amba_port { struct vendor_data { unsigned int ifls; unsigned int fifosize; + unsigned int lcrh_tx; + unsigned int lcrh_rx; }; static struct vendor_data vendor_arm = { .ifls = UART011_IFLS_RX4_8|UART011_IFLS_TX4_8, .fifosize = 16, + .lcrh_tx = UART011_LCRH, + .lcrh_rx = UART011_LCRH, }; static struct vendor_data vendor_st = { .ifls = UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF, .fifosize = 64, + .lcrh_tx = ST_UART011_LCRH_TX, + .lcrh_rx = ST_UART011_LCRH_RX, }; static void pl011_stop_tx(struct uart_port *port) @@ -327,12 +335,12 @@ static void pl011_break_ctl(struct uart_port *port, int break_state) unsigned int lcr_h; spin_lock_irqsave(&uap->port.lock, flags); - lcr_h = readw(uap->port.membase + UART011_LCRH); + lcr_h = readw(uap->port.membase + uap->lcrh_tx); if (break_state == -1) lcr_h |= UART01x_LCRH_BRK; else lcr_h &= ~UART01x_LCRH_BRK; - writew(lcr_h, uap->port.membase + UART011_LCRH); + writew(lcr_h, uap->port.membase + uap->lcrh_tx); spin_unlock_irqrestore(&uap->port.lock, flags); } @@ -393,7 +401,17 @@ static int pl011_startup(struct uart_port *port) writew(cr, uap->port.membase + UART011_CR); writew(0, uap->port.membase + UART011_FBRD); writew(1, uap->port.membase + UART011_IBRD); - writew(0, uap->port.membase + UART011_LCRH); + writew(0, uap->port.membase + uap->lcrh_rx); + if (uap->lcrh_tx != uap->lcrh_rx) { + int i; + /* + * Wait 10 PCLKs before writing LCRH_TX register, + * to get this delay write read only register 10 times + */ + for (i = 0; i < 10; ++i) + writew(0xff, uap->port.membase + UART011_MIS); + writew(0, uap->port.membase + uap->lcrh_tx); + } writew(0, uap->port.membase + UART01x_DR); while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY) barrier(); @@ -422,10 +440,19 @@ static int pl011_startup(struct uart_port *port) return retval; } +static void pl011_shutdown_channel(struct uart_amba_port *uap, + unsigned int lcrh) +{ + unsigned long val; + + val = readw(uap->port.membase + lcrh); + val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN); + writew(val, uap->port.membase + lcrh); +} + static void pl011_shutdown(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; - unsigned long val; /* * disable all interrupts @@ -450,9 +477,9 @@ static void pl011_shutdown(struct uart_port *port) /* * disable break condition and fifos */ - val = readw(uap->port.membase + UART011_LCRH); - val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN); - writew(val, uap->port.membase + UART011_LCRH); + pl011_shutdown_channel(uap, uap->lcrh_rx); + if (uap->lcrh_rx != uap->lcrh_tx) + pl011_shutdown_channel(uap, uap->lcrh_tx); /* * Shut down the clock producer @@ -561,7 +588,17 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios, * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L * ----------^----------^----------^----------^----- */ - writew(lcr_h, port->membase + UART011_LCRH); + writew(lcr_h, port->membase + uap->lcrh_rx); + if (uap->lcrh_rx != uap->lcrh_tx) { + int i; + /* + * Wait 10 PCLKs before writing LCRH_TX register, + * to get this delay write read only register 10 times + */ + for (i = 0; i < 10; ++i) + writew(0xff, uap->port.membase + UART011_MIS); + writew(lcr_h, port->membase + uap->lcrh_tx); + } writew(old_cr, port->membase + UART011_CR); spin_unlock_irqrestore(&port->lock, flags); @@ -688,7 +725,7 @@ pl011_console_get_options(struct uart_amba_port *uap, int *baud, if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) { unsigned int lcr_h, ibrd, fbrd; - lcr_h = readw(uap->port.membase + UART011_LCRH); + lcr_h = readw(uap->port.membase + uap->lcrh_tx); *parity = 'n'; if (lcr_h & UART01x_LCRH_PEN) { @@ -800,6 +837,8 @@ static int pl011_probe(struct amba_device *dev, struct amba_id *id) } uap->ifls = vendor->ifls; + uap->lcrh_rx = vendor->lcrh_rx; + uap->lcrh_tx = vendor->lcrh_tx; uap->port.dev = &dev->dev; uap->port.mapbase = dev->res.start; uap->port.membase = base; diff --git a/include/linux/amba/serial.h b/include/linux/amba/serial.h index 5a5a7fd62490..93c96a66c518 100644 --- a/include/linux/amba/serial.h +++ b/include/linux/amba/serial.h @@ -38,10 +38,12 @@ #define UART01x_FR 0x18 /* Flag register (Read only). */ #define UART010_IIR 0x1C /* Interrupt indentification register (Read). */ #define UART010_ICR 0x1C /* Interrupt clear register (Write). */ +#define ST_UART011_LCRH_RX 0x1C /* Rx line control register. */ #define UART01x_ILPR 0x20 /* IrDA low power counter register. */ #define UART011_IBRD 0x24 /* Integer baud rate divisor register. */ #define UART011_FBRD 0x28 /* Fractional baud rate divisor register. */ #define UART011_LCRH 0x2c /* Line control register. */ +#define ST_UART011_LCRH_TX 0x2c /* Tx Line control register. */ #define UART011_CR 0x30 /* Control register. */ #define UART011_IFLS 0x34 /* Interrupt fifo level select. */ #define UART011_IMSC 0x38 /* Interrupt mask. */