From patchwork Mon Sep 27 13:37:11 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sukumar Ghorai X-Patchwork-Id: 212492 X-Patchwork-Delegate: tony@atomide.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o8RDc3Wb023418 for ; Mon, 27 Sep 2010 13:38:05 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759353Ab0I0Nhe (ORCPT ); Mon, 27 Sep 2010 09:37:34 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:41022 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759341Ab0I0Nh1 (ORCPT ); Mon, 27 Sep 2010 09:37:27 -0400 Received: from dbdp31.itg.ti.com ([172.24.170.98]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id o8RDbK4u024895 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 27 Sep 2010 08:37:22 -0500 Received: from localhost.localdomain (localhost [127.0.0.1]) by dbdp31.itg.ti.com (8.13.8/8.13.8) with ESMTP id o8RDbEb2013234; Mon, 27 Sep 2010 19:07:18 +0530 (IST) From: Sukumar Ghorai To: linux-omap@vger.kernel.org Cc: linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Sukumar Ghorai , Vimal Singh Subject: [PATCH v5 2/5] omap3: nand: prefetch in irq mode support Date: Mon, 27 Sep 2010 19:07:11 +0530 Message-Id: <1285594634-19277-3-git-send-email-s-ghorai@ti.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1285594634-19277-1-git-send-email-s-ghorai@ti.com> References: <1285594634-19277-1-git-send-email-s-ghorai@ti.com> Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Mon, 27 Sep 2010 13:38:05 +0000 (UTC) diff --git a/arch/arm/mach-omap2/board-flash.c b/arch/arm/mach-omap2/board-flash.c index ac834aa..2355e4a 100644 --- a/arch/arm/mach-omap2/board-flash.c +++ b/arch/arm/mach-omap2/board-flash.c @@ -17,6 +17,7 @@ #include #include +#include #include #include #include @@ -142,8 +143,9 @@ __init board_nand_init(struct mtd_partition *nand_parts, u8 nr_parts, u8 cs) { board_nand_data.cs = cs; board_nand_data.parts = nand_parts; - board_nand_data.nr_parts = nr_parts; + board_nand_data.nr_parts = nr_parts; + board_nand_data.gpmc_irq = OMAP_GPMC_IRQ_BASE + cs; gpmc_nand_init(&board_nand_data); } #else diff --git a/arch/arm/plat-omap/include/plat/nand.h b/arch/arm/plat-omap/include/plat/nand.h index 6562cd0..5e69463 100644 --- a/arch/arm/plat-omap/include/plat/nand.h +++ b/arch/arm/plat-omap/include/plat/nand.h @@ -20,6 +20,7 @@ struct omap_nand_platform_data { int (*nand_setup)(void); int (*dev_ready)(struct omap_nand_platform_data *); int dma_channel; + int gpmc_irq; unsigned long phys_base; int devsize; }; diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 8b4b67c..88cea0c 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -112,6 +112,9 @@ config MTD_NAND_OMAP_PREFETCH help The NAND device can be accessed for Read/Write using GPMC PREFETCH engine to improve the performance. + GPMC PREFETCH can be configured eigther in MPU interrupt mode or in DMA + interrupt mode. If not selected any of them prefetch will be used in + polling mode. config MTD_NAND_OMAP_PREFETCH_DMA depends on MTD_NAND_OMAP_PREFETCH @@ -120,7 +123,16 @@ config MTD_NAND_OMAP_PREFETCH_DMA help The GPMC PREFETCH engine can be configured eigther in MPU interrupt mode or in DMA interrupt mode. - Say y for DMA mode or MPU mode will be used + Say y for DMA mode + +config MTD_NAND_OMAP_PREFETCH_IRQ + depends on MTD_NAND_OMAP_PREFETCH && !MTD_NAND_OMAP_PREFETCH_DMA + bool "IRQ mode" + default n + help + The GPMC PREFETCH engine can be configured eigther in MPU interrupt mode + or in DMA interrupt mode. + Say y for IRQ mode config MTD_NAND_IDS tristate diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 133d515..72994e8 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -105,17 +106,27 @@ module_param(use_prefetch, bool, 0); MODULE_PARM_DESC(use_prefetch, "enable/disable use of PREFETCH"); #ifdef CONFIG_MTD_NAND_OMAP_PREFETCH_DMA +const int use_interrupt; static int use_dma = 1; /* "modprobe ... use_dma=0" etc */ module_param(use_dma, bool, 0); -MODULE_PARM_DESC(use_dma, "enable/disable use of DMA"); +MODULE_PARM_DESC(use_dma, "enable/disable use of DMA mode"); +#elif defined(CONFIG_MTD_NAND_OMAP_PREFETCH_IRQ) +const int use_dma; +static int use_interrupt = 1; + +/* "modprobe ... use_dma=0" etc */ +module_param(use_interrupt, bool, 0); +MODULE_PARM_DESC(use_interrupt, "enable/disable use of IRQ mode"); #else const int use_dma; +const int use_interrupt; #endif #else const int use_prefetch; const int use_dma; +const int use_interrupt; #endif struct omap_nand_info { @@ -130,6 +141,13 @@ struct omap_nand_info { unsigned long phys_base; struct completion comp; int dma_ch; + int gpmc_irq; + enum { + OMAP_NAND_IO_READ = 0, /* read */ + OMAP_NAND_IO_WRITE, /* write */ + } iomode; + u_char *buf; + int buf_len; }; /** @@ -467,6 +485,153 @@ static void omap_write_buf_dma_pref(struct mtd_info *mtd, omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1); } +/* + * omap_nand_irq - GMPC irq handler + * @this_irq: gpmc irq number + * @dev: omap_nand_info structure pointer is passed here + */ +static irqreturn_t omap_nand_irq(int this_irq, void *dev) +{ + struct omap_nand_info *info = (struct omap_nand_info *) dev; + u32 bytes; + u32 irq_stat; + + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); + bytes = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT); + bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */ + if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */ + if (irq_stat & 0x2) + goto done; + + if (info->buf_len & (info->buf_len < bytes)) + bytes = info->buf_len; + else if (!info->buf_len) + bytes = 0; + iowrite32_rep(info->nand.IO_ADDR_W, + (u32 *)info->buf, bytes >> 2); + info->buf = info->buf + bytes; + info->buf_len -= bytes; + + } else { + ioread32_rep(info->nand.IO_ADDR_R, + (u32 *)info->buf, bytes >> 2); + info->buf = info->buf + bytes; + + if (irq_stat & 0x2) + goto done; + } + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); + + return IRQ_HANDLED; + +done: + complete(&info->comp); + /* disable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, 0); + + /* clear status */ + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); + + return IRQ_HANDLED; +} + +/* + * omap_read_buf_irq_pref - read data from NAND controller into buffer + * @mtd: MTD device structure + * @buf: buffer to store date + * @len: number of bytes to read + */ +static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len) +{ + struct omap_nand_info *info = container_of(mtd, + struct omap_nand_info, mtd); + int ret = 0; + + if (len <= mtd->oobsize) { + omap_read_buf_pref(mtd, buf, len); + return; + } + + info->iomode = OMAP_NAND_IO_READ; + info->buf = buf; + init_completion(&info->comp); + + /* configure and start prefetch transfer */ + ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x0); + if (ret) + /* PFPW engine is busy, use cpu copy methode */ + goto out_copy; + + info->buf_len = len; + /* enable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, + (GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT)); + + /* waiting for read to complete */ + wait_for_completion(&info->comp); + + /* disable and stop the PFPW engine */ + gpmc_prefetch_reset(info->gpmc_cs); + return; + +out_copy: + if (info->nand.options & NAND_BUSWIDTH_16) + omap_read_buf16(mtd, buf, len); + else + omap_read_buf8(mtd, buf, len); +} + +/* + * omap_write_buf_irq_pref - write buffer to NAND controller + * @mtd: MTD device structure + * @buf: data buffer + * @len: number of bytes to write + */ +static void omap_write_buf_irq_pref(struct mtd_info *mtd, + const u_char *buf, int len) +{ + struct omap_nand_info *info = container_of(mtd, + struct omap_nand_info, mtd); + int ret = 0; + if (len <= mtd->oobsize) { + omap_write_buf_pref(mtd, buf, len); + return; + } + + info->iomode = OMAP_NAND_IO_WRITE; + info->buf = (u_char *) buf; + init_completion(&info->comp); + + /* configure and start prefetch transfer */ + ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x1); + if (ret) + /* PFPW engine is busy, use cpu copy methode */ + goto out_copy; + + info->buf_len = len; + /* enable irq */ + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, + (GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT)); + + /* waiting for write to complete */ + wait_for_completion(&info->comp); + /* wait for data to flushed-out before reset the prefetch */ + do { + ret = gpmc_read_status(GPMC_PREFETCH_COUNT); + } while (ret); + /* disable and stop the PFPW engine */ + gpmc_prefetch_reset(info->gpmc_cs); + return; + +out_copy: + if (info->nand.options & NAND_BUSWIDTH_16) + omap_write_buf16(mtd, buf, len); + else + omap_write_buf8(mtd, buf, len); +} + /** * omap_verify_buf - Verify chip data against buffer * @mtd: MTD device structure @@ -800,6 +965,7 @@ static int __devinit omap_nand_probe(struct platform_device *pdev) info->gpmc_cs = pdata->cs; info->phys_base = pdata->phys_base; + info->gpmc_irq = pdata->gpmc_irq; info->mtd.priv = &info->nand; info->mtd.name = dev_name(&pdev->dev); @@ -863,7 +1029,19 @@ static int __devinit omap_nand_probe(struct platform_device *pdev) info->nand.read_buf = omap_read_buf_dma_pref; info->nand.write_buf = omap_write_buf_dma_pref; } + } else if (use_interrupt) { + err = request_irq(info->gpmc_irq, omap_nand_irq, + IRQF_SHARED, "gpmc-nand", info); + if (err) { + printk(KERN_INFO "requesting irq %i. err %d" + " Prefetch will work in mpu poling mode\n", + info->gpmc_irq, err); + } else { + info->nand.read_buf = omap_read_buf_irq_pref; + info->nand.write_buf = omap_write_buf_irq_pref; + } } + } else { if (info->nand.options & NAND_BUSWIDTH_16) { info->nand.read_buf = omap_read_buf16; @@ -953,11 +1131,19 @@ static int __init omap_nand_init(void) /* This check is required if driver is being * loaded run time as a module */ - if ((1 == use_dma) && (0 == use_prefetch)) { - printk(KERN_INFO"Wrong parameters: 'use_dma' can not be 1 " - "without use_prefetch'. Prefetch will not be" - " used in either mode (mpu or dma)\n"); + + if ((0 == use_prefetch) && (1 == (use_dma | use_interrupt))) { + printk(KERN_INFO "Wrong parameters: Neither 'dma' nor 'irq' " + "can used without 'use_prefetch' selected.\n"); + printk(KERN_INFO "Prefetch will not be used in any mode: " + "poll, mpu or dma\n"); + } else if ((1 == use_prefetch) && (1 == (use_interrupt & use_dma))) { + printk(KERN_INFO "Wrong parameters: Both DMA and IRQ" + " modes can not be used together.\n"); + printk(KERN_INFO "It has to be selected at compile " + "time and same will be used.\n"); } + return platform_driver_register(&omap_nand_driver); }