Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933039AbXBESqP (ORCPT ); Mon, 5 Feb 2007 13:46:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933035AbXBESqP (ORCPT ); Mon, 5 Feb 2007 13:46:15 -0500 Received: from father.pmc-sierra.com ([216.241.224.13]:47046 "HELO father.pmc-sierra.bc.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933039AbXBESqN (ORCPT ); Mon, 5 Feb 2007 13:46:13 -0500 Message-ID: <45C77B61.1080209@pmc-sierra.com> From: Marc St-Jean To: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-mips@linux-mips.org Subject: [PATCH] serial driver PMC MSP71xx, kernel linux-mips.git master Date: Mon, 5 Feb 2007 10:45:53 -0800 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) x-originalarrivaltime: 05 Feb 2007 18:45:53.0270 (UTC) FILETIME=[DD083960:01C74955] user-agent: Thunderbird 1.5.0.9 (X11/20061206) Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6085 Lines: 178 Third attempt at the serial driver patch for the PMC-Sierra MSP71xx device. There are three different fixes: 1. Fix for DesignWare THRE errata - Dropped our fix since the "8250-uart-backup-timer.patch" in the "mm" tree also fixes it. This patch needs to be applied on top of it. 2. Fix for Busy Detect on LCR write - Dropped the addition of UPIO_DWAPB iotype to 8250_early.c as Sergei pointed out the fix wasn't complete and we don't require it. 3. Workaround for interrupt/data concurrency issue - Fix must remain serial8250_interrupt() in order to mark interrupt as handled. Thanks, Marc Signed-off-by: Marc St-Jean diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 3d91bfc..489ff2b 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -308,6 +308,7 @@ static unsigned int serial_in(struct uar return inb(up->port.iobase + 1); case UPIO_MEM: + case UPIO_DWAPB: return readb(up->port.membase + offset); case UPIO_MEM32: @@ -333,6 +334,8 @@ #endif static void serial_out(struct uart_8250_port *up, int offset, int value) { + /* Save the offset before it's remapped */ + int save_offset = offset; offset = map_8250_out_reg(up, offset) << up->port.regshift; switch (up->port.iotype) { @@ -359,6 +362,18 @@ #endif writeb(value, up->port.membase + offset); break; + case UPIO_DWAPB: + /* Save the LCR value so it can be re-written when a + * Busy Detect interrupt occurs. */ + if (save_offset == UART_LCR) + up->lcr = value; + writeb(value, up->port.membase + offset); + /* Read the IER to ensure any interrupt is cleared before + * returning from ISR. */ + if ((save_offset == UART_TX || save_offset == UART_IER) && in_irq()) + value = serial_in(up, UART_IER); + break; + default: outb(value, up->port.iobase + offset); } @@ -373,6 +388,7 @@ serial_out_sync(struct uart_8250_port *u #ifdef CONFIG_SERIAL_8250_AU1X00 case UPIO_AU: #endif + case UPIO_DWAPB: serial_out(up, offset, value); (void)serial_in(up, UART_LCR); /* safe, no side-effects */ break; @@ -1383,6 +1399,19 @@ static irqreturn_t serial8250_interrupt( handled = 1; end = NULL; + } else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY && + up->port.iotype == UPIO_DWAPB) { + /* The DesignWare APB UART has an Busy Detect (0x07) + * interrupt meaning an LCR write attempt occured while the + * UART was busy. The interrupt must be cleared by reading + * the UART status register (USR) and the LCR re-written. */ + unsigned int status; + status = *(volatile u32 *)up->port.data; + serial_out(up, UART_LCR, up->lcr); + + handled = 1; + + end = NULL; } else if (end == NULL) end = l; @@ -2085,6 +2114,7 @@ static int serial8250_request_std_resour case UPIO_TSI: case UPIO_MEM32: case UPIO_MEM: + case UPIO_DWAPB: if (!up->port.mapbase) break; @@ -2122,6 +2152,7 @@ static void serial8250_release_std_resou case UPIO_TSI: case UPIO_MEM32: case UPIO_MEM: + case UPIO_DWAPB: if (!up->port.mapbase) break; @@ -2454,9 +2485,12 @@ int __init serial8250_start_console(stru add_preferred_console("ttyS", line, options); printk("Adding console on ttyS%d at %s 0x%lx (options '%s')\n", - line, port->iotype == UPIO_MEM ? "MMIO" : "I/O port", - port->iotype == UPIO_MEM ? (unsigned long) port->mapbase : - (unsigned long) port->iobase, options); + line, + (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) + ? "MMIO" : "I/O port", + (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) + ? (unsigned long) port->mapbase : (unsigned long) port->iobase, + options); if (!(serial8250_console.flags & CON_ENABLED)) { serial8250_console.flags &= ~CON_PRINTBUFFER; register_console(&serial8250_console); diff --git a/drivers/serial/8250.h b/drivers/serial/8250.h diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index f84982e..f5b6036 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -2057,6 +2057,7 @@ uart_report_port(struct uart_driver *drv case UPIO_MEM32: case UPIO_AU: case UPIO_TSI: + case UPIO_DWAPB: snprintf(address, sizeof(address), "MMIO 0x%lx", port->mapbase); break; @@ -2401,6 +2402,7 @@ int uart_match_port(struct uart_port *po case UPIO_MEM32: case UPIO_AU: case UPIO_TSI: + case UPIO_DWAPB: return (port1->mapbase == port2->mapbase); } return 0; diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index cf23813..9cb9b3b 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -230,6 +230,7 @@ #define UPIO_MEM (2) #define UPIO_MEM32 (3) #define UPIO_AU (4) /* Au1x00 type IO */ #define UPIO_TSI (5) /* Tsi108/109 type IO */ +#define UPIO_DWAPB (6) /* DesignWare APB UART */ unsigned int read_status_mask; /* driver specific */ unsigned int ignore_status_mask; /* driver specific */ @@ -276,6 +277,7 @@ #define UPF_USR_MASK ((__force upf_t) ( struct device *dev; /* parent device */ unsigned char hub6; /* this should be in the 8250 driver */ unsigned char unused[3]; + void *data; /* generic platform data pointer */ }; /* diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h index 3c8a6aa..b3550cc 100644 --- a/include/linux/serial_reg.h +++ b/include/linux/serial_reg.h @@ -37,6 +37,7 @@ #define UART_IIR_MSI 0x00 /* Modem stat #define UART_IIR_THRI 0x02 /* Transmitter holding register empty */ #define UART_IIR_RDI 0x04 /* Receiver data interrupt */ #define UART_IIR_RLSI 0x06 /* Receiver line status interrupt */ +#define UART_IIR_BUSY 0x07 /* DesignWare APB Busy Detect */ #define UART_FCR 2 /* Out: FIFO Control Register */ #define UART_FCR_ENABLE_FIFO 0x01 /* Enable the FIFO */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/