From 0bcfd70ea11a5d6f2362be463513a60245a62baf Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 24 Dec 2007 19:40:05 +0800 Subject: [PATCH] [Blackfin] serial driver: fix bug - cache the bits of the LSR on systems where the LSR is read-to-clear Cache the bits of the LSR on systems where the LSR is read-to-clear so that we can safely read the LSR in random places. this fixes older parts where break/framing/parity/overflow was not being detected at all in PIO mode, and this fixes newer parts where break/framing/parity/overflow was being reported all the time without being cleared. Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu --- drivers/serial/bfin_5xx.c | 10 +++++++--- .../asm-blackfin/mach-bf527/bfin_serial_5xx.h | 19 ++++++++++++++++++- .../asm-blackfin/mach-bf533/bfin_serial_5xx.h | 19 ++++++++++++++++++- .../asm-blackfin/mach-bf537/bfin_serial_5xx.h | 19 ++++++++++++++++++- .../asm-blackfin/mach-bf548/bfin_serial_5xx.h | 1 + .../asm-blackfin/mach-bf561/bfin_serial_5xx.h | 19 ++++++++++++++++++- 6 files changed, 80 insertions(+), 7 deletions(-) diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c index ca9ceaa113..af84984df7 100644 --- a/drivers/serial/bfin_5xx.c +++ b/drivers/serial/bfin_5xx.c @@ -216,8 +216,10 @@ static void bfin_serial_rx_chars(struct bfin_serial_port *uart) struct pt_regs *regs = get_irq_regs(); #endif - ch = UART_GET_CHAR(uart); status = UART_GET_LSR(uart); + UART_CLEAR_LSR(uart); + + ch = UART_GET_CHAR(uart); uart->port.icount.rx++; #ifdef CONFIG_KGDB_UART @@ -335,7 +337,7 @@ static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id) struct bfin_serial_port *uart = dev_id; spin_lock(&uart->port.lock); - while ((UART_GET_IER(uart) & ERBFI) && (UART_GET_LSR(uart) & DR)) + while (UART_GET_LSR(uart) & DR) bfin_serial_rx_chars(uart); spin_unlock(&uart->port.lock); @@ -347,7 +349,7 @@ static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id) struct bfin_serial_port *uart = dev_id; spin_lock(&uart->port.lock); - if ((UART_GET_IER(uart) & ETBEI) && (UART_GET_LSR(uart) & THRE)) + if (UART_GET_LSR(uart) & THRE) bfin_serial_tx_chars(uart); spin_unlock(&uart->port.lock); @@ -428,6 +430,8 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart) int i, flg, status; status = UART_GET_LSR(uart); + UART_CLEAR_LSR(uart); + uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);; if (status & BI) { diff --git a/include/asm-blackfin/mach-bf527/bfin_serial_5xx.h b/include/asm-blackfin/mach-bf527/bfin_serial_5xx.h index 15dbc21eed..233c585efc 100644 --- a/include/asm-blackfin/mach-bf527/bfin_serial_5xx.h +++ b/include/asm-blackfin/mach-bf527/bfin_serial_5xx.h @@ -23,7 +23,6 @@ #define UART_GET_DLH(uart) bfin_read16(((uart)->port.membase + OFFSET_DLH)) #define UART_GET_IIR(uart) bfin_read16(((uart)->port.membase + OFFSET_IIR)) #define UART_GET_LCR(uart) bfin_read16(((uart)->port.membase + OFFSET_LCR)) -#define UART_GET_LSR(uart) bfin_read16(((uart)->port.membase + OFFSET_LSR)) #define UART_GET_GCTL(uart) bfin_read16(((uart)->port.membase + OFFSET_GCTL)) #define UART_PUT_CHAR(uart, v) bfin_write16(((uart)->port.membase + OFFSET_THR), v) @@ -58,6 +57,7 @@ struct bfin_serial_port { struct uart_port port; unsigned int old_status; + unsigned int lsr; #ifdef CONFIG_SERIAL_BFIN_DMA int tx_done; int tx_count; @@ -76,6 +76,23 @@ struct bfin_serial_port { #endif }; +/* The hardware clears the LSR bits upon read, so we need to cache + * some of the more fun bits in software so they don't get lost + * when checking the LSR in other code paths (TX). + */ +static inline unsigned int UART_GET_LSR(struct bfin_serial_port *uart) +{ + unsigned int lsr = bfin_read16(uart->port.membase + OFFSET_LSR); + uart->lsr |= (lsr & (BI|FE|PE|OE)); + return lsr | uart->lsr; +} + +static inline void UART_CLEAR_LSR(struct bfin_serial_port *uart) +{ + uart->lsr = 0; + bfin_write16(uart->port.membase + OFFSET_LSR, -1); +} + struct bfin_serial_port bfin_serial_ports[NR_PORTS]; struct bfin_serial_res { unsigned long uart_base_addr; diff --git a/include/asm-blackfin/mach-bf533/bfin_serial_5xx.h b/include/asm-blackfin/mach-bf533/bfin_serial_5xx.h index 7871d4313f..b619065cee 100644 --- a/include/asm-blackfin/mach-bf533/bfin_serial_5xx.h +++ b/include/asm-blackfin/mach-bf533/bfin_serial_5xx.h @@ -23,7 +23,6 @@ #define UART_GET_DLH(uart) bfin_read16(((uart)->port.membase + OFFSET_DLH)) #define UART_GET_IIR(uart) bfin_read16(((uart)->port.membase + OFFSET_IIR)) #define UART_GET_LCR(uart) bfin_read16(((uart)->port.membase + OFFSET_LCR)) -#define UART_GET_LSR(uart) bfin_read16(((uart)->port.membase + OFFSET_LSR)) #define UART_GET_GCTL(uart) bfin_read16(((uart)->port.membase + OFFSET_GCTL)) #define UART_PUT_CHAR(uart,v) bfin_write16(((uart)->port.membase + OFFSET_THR),v) @@ -46,6 +45,7 @@ struct bfin_serial_port { struct uart_port port; unsigned int old_status; + unsigned int lsr; #ifdef CONFIG_SERIAL_BFIN_DMA int tx_done; int tx_count; @@ -64,6 +64,23 @@ struct bfin_serial_port { #endif }; +/* The hardware clears the LSR bits upon read, so we need to cache + * some of the more fun bits in software so they don't get lost + * when checking the LSR in other code paths (TX). + */ +static inline unsigned int UART_GET_LSR(struct bfin_serial_port *uart) +{ + unsigned int lsr = bfin_read16(uart->port.membase + OFFSET_LSR); + uart->lsr |= (lsr & (BI|FE|PE|OE)); + return lsr | uart->lsr; +} + +static inline void UART_CLEAR_LSR(struct bfin_serial_port *uart) +{ + uart->lsr = 0; + bfin_write16(uart->port.membase + OFFSET_LSR, -1); +} + struct bfin_serial_port bfin_serial_ports[NR_PORTS]; struct bfin_serial_res { unsigned long uart_base_addr; diff --git a/include/asm-blackfin/mach-bf537/bfin_serial_5xx.h b/include/asm-blackfin/mach-bf537/bfin_serial_5xx.h index 86e45c3798..f18c517cc9 100644 --- a/include/asm-blackfin/mach-bf537/bfin_serial_5xx.h +++ b/include/asm-blackfin/mach-bf537/bfin_serial_5xx.h @@ -23,7 +23,6 @@ #define UART_GET_DLH(uart) bfin_read16(((uart)->port.membase + OFFSET_DLH)) #define UART_GET_IIR(uart) bfin_read16(((uart)->port.membase + OFFSET_IIR)) #define UART_GET_LCR(uart) bfin_read16(((uart)->port.membase + OFFSET_LCR)) -#define UART_GET_LSR(uart) bfin_read16(((uart)->port.membase + OFFSET_LSR)) #define UART_GET_GCTL(uart) bfin_read16(((uart)->port.membase + OFFSET_GCTL)) #define UART_PUT_CHAR(uart,v) bfin_write16(((uart)->port.membase + OFFSET_THR),v) @@ -58,6 +57,7 @@ struct bfin_serial_port { struct uart_port port; unsigned int old_status; + unsigned int lsr; #ifdef CONFIG_SERIAL_BFIN_DMA int tx_done; int tx_count; @@ -76,6 +76,23 @@ struct bfin_serial_port { #endif }; +/* The hardware clears the LSR bits upon read, so we need to cache + * some of the more fun bits in software so they don't get lost + * when checking the LSR in other code paths (TX). + */ +static inline unsigned int UART_GET_LSR(struct bfin_serial_port *uart) +{ + unsigned int lsr = bfin_read16(uart->port.membase + OFFSET_LSR); + uart->lsr |= (lsr & (BI|FE|PE|OE)); + return lsr | uart->lsr; +} + +static inline void UART_CLEAR_LSR(struct bfin_serial_port *uart) +{ + uart->lsr = 0; + bfin_write16(uart->port.membase + OFFSET_LSR, -1); +} + struct bfin_serial_port bfin_serial_ports[NR_PORTS]; struct bfin_serial_res { unsigned long uart_base_addr; diff --git a/include/asm-blackfin/mach-bf548/bfin_serial_5xx.h b/include/asm-blackfin/mach-bf548/bfin_serial_5xx.h index 3770aa38ee..8733d47747 100644 --- a/include/asm-blackfin/mach-bf548/bfin_serial_5xx.h +++ b/include/asm-blackfin/mach-bf548/bfin_serial_5xx.h @@ -32,6 +32,7 @@ #define UART_PUT_DLH(uart,v) bfin_write16(((uart)->port.membase + OFFSET_DLH),v) #define UART_PUT_LSR(uart,v) bfin_write16(((uart)->port.membase + OFFSET_LSR),v) #define UART_PUT_LCR(uart,v) bfin_write16(((uart)->port.membase + OFFSET_LCR),v) +#define UART_CLEAR_LSR(uart) bfin_write16(((uart)->port.membase + OFFSET_LSR), -1) #define UART_PUT_GCTL(uart,v) bfin_write16(((uart)->port.membase + OFFSET_GCTL),v) #if defined(CONFIG_BFIN_UART0_CTSRTS) || defined(CONFIG_BFIN_UART1_CTSRTS) diff --git a/include/asm-blackfin/mach-bf561/bfin_serial_5xx.h b/include/asm-blackfin/mach-bf561/bfin_serial_5xx.h index 7871d4313f..b619065cee 100644 --- a/include/asm-blackfin/mach-bf561/bfin_serial_5xx.h +++ b/include/asm-blackfin/mach-bf561/bfin_serial_5xx.h @@ -23,7 +23,6 @@ #define UART_GET_DLH(uart) bfin_read16(((uart)->port.membase + OFFSET_DLH)) #define UART_GET_IIR(uart) bfin_read16(((uart)->port.membase + OFFSET_IIR)) #define UART_GET_LCR(uart) bfin_read16(((uart)->port.membase + OFFSET_LCR)) -#define UART_GET_LSR(uart) bfin_read16(((uart)->port.membase + OFFSET_LSR)) #define UART_GET_GCTL(uart) bfin_read16(((uart)->port.membase + OFFSET_GCTL)) #define UART_PUT_CHAR(uart,v) bfin_write16(((uart)->port.membase + OFFSET_THR),v) @@ -46,6 +45,7 @@ struct bfin_serial_port { struct uart_port port; unsigned int old_status; + unsigned int lsr; #ifdef CONFIG_SERIAL_BFIN_DMA int tx_done; int tx_count; @@ -64,6 +64,23 @@ struct bfin_serial_port { #endif }; +/* The hardware clears the LSR bits upon read, so we need to cache + * some of the more fun bits in software so they don't get lost + * when checking the LSR in other code paths (TX). + */ +static inline unsigned int UART_GET_LSR(struct bfin_serial_port *uart) +{ + unsigned int lsr = bfin_read16(uart->port.membase + OFFSET_LSR); + uart->lsr |= (lsr & (BI|FE|PE|OE)); + return lsr | uart->lsr; +} + +static inline void UART_CLEAR_LSR(struct bfin_serial_port *uart) +{ + uart->lsr = 0; + bfin_write16(uart->port.membase + OFFSET_LSR, -1); +} + struct bfin_serial_port bfin_serial_ports[NR_PORTS]; struct bfin_serial_res { unsigned long uart_base_addr; -- 2.39.5