Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750983AbXAYAAy (ORCPT ); Wed, 24 Jan 2007 19:00:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752098AbXAYAAy (ORCPT ); Wed, 24 Jan 2007 19:00:54 -0500 Received: from mother.pmc-sierra.com ([216.241.224.12]:58362 "HELO mother.pmc-sierra.bc.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750983AbXAYAAx (ORCPT ); Wed, 24 Jan 2007 19:00:53 -0500 Message-ID: <45B7F32E.1030208@pmc-sierra.com> From: Marc St-Jean To: linux-mips@linux-mips.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] serial driver PMC MSP71xx, kernel linux-mips.git master Date: Wed, 24 Jan 2007 16:00:46 -0800 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) x-originalarrivaltime: 25 Jan 2007 00:00:46.0784 (UTC) FILETIME=[DD7CAC00:01C74013] 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: 10453 Lines: 312 Here is my second attempt at the serial driver patch for the PMC-Sierra MSP71xx device. There are three different fixes: 1. Fix for THRE errata - I verified the UART_BUG_TXEN fix does not help with this erratum. - I left our current fix in until I get our platform booting on 2.6.20-rc4 to try the mm tree "8250-uart-backup-timer.patch". Feel free to ignore for now. 2. Fix for Busy Detect on LCR write - Moved to new UPIO_DWAPB iotype. Because the new type is a memory mapped device and there are several tests for UPIO_MEM, this involved updating serial_core.c and 8250_early.c in addition to 8250.c. - I tried implementing this totally in serial_in as suggested, but it can't be done because of bit overlap between UART_IIR_NO_INT and UART_IIR_BUSY. Also there is no way to set the interrupt "handled = 1" from serial_in. 3. Workaround for interrupt/data concurrency issue - Moved to new UPIO_DWAPB iotype. Thanks, Marc Signed-off-by: Marc St-Jean Index: linux_2_6/drivers/serial/8250.c =================================================================== RCS file: linux_2_6/drivers/serial/8250.c,v retrieving revision 1.1.1.7 diff -u -r1.1.1.7 8250.c --- linux_2_6/drivers/serial/8250.c 19 Oct 2006 21:00:58 -0000 1.1.1.7 +++ linux_2_6/drivers/serial/8250.c 24 Jan 2007 23:55:27 -0000 @@ -308,6 +308,7 @@ 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 @@ 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 +362,19 @@ 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); } @@ -1016,6 +1032,17 @@ up->bugs |= UART_BUG_NOMSR; #endif + /* Workaround: + * The DesignWare SoC UART part has a bug for all + * versions before 3.03a (2005-07-18) + * In brief, this is a non-standard 16550 in that the THRE interrupt + * will not re-assert itself simply by disabling and re-enabling the + * THRI bit in the IER, it is only re-enabled if a character is actually + * sent out. + */ + if( up->port.flags & UPF_DW_THRE_BUG ) + up->bugs |= UART_BUG_DWTHRE; + serial_outp(up, UART_LCR, save_lcr); if (up->capabilities != uart_config[up->port.type].flags) { @@ -1141,6 +1168,12 @@ iir = serial_in(up, UART_IIR); if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) transmit_chars(up); + } else if (up->bugs & UART_BUG_DWTHRE) { + unsigned char lsr, iir; + lsr = serial_in(up, UART_LSR); + iir = serial_in(up, UART_IIR); + if (lsr & UART_LSR_THRE) + transmit_chars(up); } } @@ -1366,6 +1399,19 @@ 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 the LCR was written while the UART + * was busy, so the LCR was not actually written. It's + * cleared by reading the extended UART status register. */ + unsigned int status; + status = *(volatile u32 *)up->port.user; + serial_out(up, UART_LCR, up->lcr); + + handled = 1; + + end = NULL; } else if (end == NULL) end = l; @@ -1950,6 +1996,7 @@ size = 0x100000; /* fall thru */ case UPIO_MEM: + case UPIO_DWAPB: if (!up->port.mapbase) break; @@ -1985,6 +2032,7 @@ size = 0x100000; /* fall thru */ case UPIO_MEM: + case UPIO_DWAPB: if (!up->port.mapbase) break; @@ -2011,6 +2059,7 @@ switch (up->port.iotype) { case UPIO_MEM: + case UPIO_DWAPB: ret = -EINVAL; break; @@ -2032,6 +2081,7 @@ switch (up->port.iotype) { case UPIO_MEM: + case UPIO_DWAPB: break; case UPIO_HUB6: @@ -2352,9 +2402,12 @@ 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); Index: linux_2_6/drivers/serial/8250.h =================================================================== RCS file: linux_2_6/drivers/serial/8250.h,v retrieving revision 1.1.1.6 retrieving revision 1.4 diff -u -r1.1.1.6 -r1.4 --- linux_2_6/drivers/serial/8250.h 19 Oct 2006 21:00:58 -0000 1.1.1.6 +++ linux_2_6/drivers/serial/8250.h 19 Oct 2006 22:08:15 -0000 1.4 @@ -49,6 +49,7 @@ #define UART_BUG_QUOT (1 << 0) /* UART has buggy quot LSB */ #define UART_BUG_TXEN (1 << 1) /* UART has buggy TX IIR status */ #define UART_BUG_NOMSR (1 << 2) /* UART has buggy MSR status bits (Au1x00) */ +#define UART_BUG_DWTHRE (1 << 3) /* UART has buggy DesignWare THRE interrupt re-assertion */ #define PROBE_RSA (1 << 0) #define PROBE_ANY (~0) Index: linux_2_6/drivers/serial/8250_early.c =================================================================== RCS file: linux_2_6/drivers/serial/8250_early.c,v retrieving revision 1.1.1.3 diff -u -r1.1.1.3 8250_early.c --- linux_2_6/drivers/serial/8250_early.c 19 Oct 2006 20:08:20 -0000 1.1.1.3 +++ linux_2_6/drivers/serial/8250_early.c 24 Jan 2007 23:55:27 -0000 @@ -46,7 +46,7 @@ static unsigned int __init serial_in(struct uart_port *port, int offset) { - if (port->iotype == UPIO_MEM) + if (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) return readb(port->membase + offset); else return inb(port->iobase + offset); @@ -54,7 +54,7 @@ static void __init serial_out(struct uart_port *port, int offset, int value) { - if (port->iotype == UPIO_MEM) + if (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) writeb(value, port->membase + offset); else outb(value, port->iobase + offset); @@ -233,7 +233,7 @@ return 0; /* Try to start the normal driver on a matching line. */ - mmio = (port->iotype == UPIO_MEM); + mmio = (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB); line = serial8250_start_console(port, device->options); if (line < 0) printk("No ttyS device at %s 0x%lx for console\n", Index: linux_2_6/drivers/serial/serial_core.c =================================================================== RCS file: linux_2_6/drivers/serial/serial_core.c,v retrieving revision 1.1.1.7 diff -u -r1.1.1.7 serial_core.c --- linux_2_6/drivers/serial/serial_core.c 19 Oct 2006 21:00:58 -0000 1.1.1.7 +++ linux_2_6/drivers/serial/serial_core.c 24 Jan 2007 23:55:28 -0000 @@ -1669,9 +1669,10 @@ ret = sprintf(buf, "%d: uart:%s %s%08lX irq:%d", port->line, uart_type(port), - port->iotype == UPIO_MEM ? "mmio:0x" : "port:", - port->iotype == UPIO_MEM ? port->mapbase : - (unsigned long) port->iobase, + (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) + ? "mmio:0x" : "port:", + (port->iotype == UPIO_MEM || port->iotype == UPIO_DWAPB) + ? port->mapbase : (unsigned long) port->iobase, port->irq); if (port->type == PORT_UNKNOWN) { @@ -2037,6 +2038,7 @@ case UPIO_MEM32: case UPIO_AU: case UPIO_TSI: + case UPIO_DWAPB: snprintf(address, sizeof(address), "MMIO 0x%lx", port->mapbase); break; @@ -2380,6 +2382,7 @@ case UPIO_MEM32: case UPIO_AU: case UPIO_TSI: + case UPIO_DWAPB: return (port1->mapbase == port2->mapbase); } return 0; Index: linux_2_6/include/linux/serial_core.h =================================================================== RCS file: linux_2_6/include/linux/serial_core.h,v retrieving revision 1.1.1.7 diff -u -r1.1.1.7 serial_core.h --- linux_2_6/include/linux/serial_core.h 19 Oct 2006 21:01:02 -0000 1.1.1.7 +++ linux_2_6/include/linux/serial_core.h 24 Jan 2007 23:55:28 -0000 @@ -228,6 +228,7 @@ #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 */ @@ -258,6 +259,8 @@ #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) #define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) #define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) +#define UPF_DW_THRE_BUG ((__force upf_t)(1 << 29)) /* DesignWare THRE hardware BUG + * (cannot be autodetected) */ #define UPF_DEAD ((__force upf_t) (1 << 30)) #define UPF_IOREMAP ((__force upf_t) (1 << 31)) @@ -274,6 +277,7 @@ struct device *dev; /* parent device */ unsigned char hub6; /* this should be in the 8250 driver */ unsigned char unused[3]; + void *user; /* generic platform 'user' pointer */ }; /* Index: linux_2_6/include/linux/serial_reg.h =================================================================== RCS file: linux_2_6/include/linux/serial_reg.h,v retrieving revision 1.1.1.2 diff -u -r1.1.1.2 serial_reg.h --- linux_2_6/include/linux/serial_reg.h 19 Oct 2006 18:29:50 -0000 1.1.1.2 +++ linux_2_6/include/linux/serial_reg.h 24 Jan 2007 23:55:29 -0000 @@ -218,6 +218,10 @@ #define UART_FCR_PXAR16 0x80 /* receive FIFO treshold = 16 */ #define UART_FCR_PXAR32 0xc0 /* receive FIFO treshold = 32 */ +/* + * DesignWare APB UART + */ +#define UART_IIR_BUSY 0x07 /* Busy Detect */ - 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/