From patchwork Mon Aug 2 15:49:50 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sukumar Ghorai X-Patchwork-Id: 116553 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o72FoBcR018168 for ; Mon, 2 Aug 2010 15:50:11 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753537Ab0HBPuI (ORCPT ); Mon, 2 Aug 2010 11:50:08 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:54049 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751893Ab0HBPuH (ORCPT ); Mon, 2 Aug 2010 11:50:07 -0400 Received: from dbdp31.itg.ti.com ([172.24.170.98]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id o72Fo2CK006375 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 2 Aug 2010 10:50:04 -0500 Received: from localhost.localdomain (localhost [127.0.0.1]) by dbdp31.itg.ti.com (8.13.8/8.13.8) with ESMTP id o72FntD3011550; Mon, 2 Aug 2010 21:19:59 +0530 (IST) From: Sukumar Ghorai To: linux-omap@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-mtd@lists.infradead.org, Sukumar Ghorai , Vimal Singh Subject: [PATCH v4 2/4] omap3: nand: configurable fifo threshold to gain the throughput Date: Mon, 2 Aug 2010 21:19:50 +0530 Message-Id: <1280764192-15053-3-git-send-email-s-ghorai@ti.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1280764192-15053-1-git-send-email-s-ghorai@ti.com> References: <1280764192-15053-1-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 (demeter.kernel.org [140.211.167.41]); Mon, 02 Aug 2010 15:50:11 +0000 (UTC) diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c index 86a6f78..8871a91 100644 --- a/arch/arm/mach-omap2/gpmc.c +++ b/arch/arm/mach-omap2/gpmc.c @@ -58,7 +58,6 @@ #define GPMC_CHUNK_SHIFT 24 /* 16 MB */ #define GPMC_SECTION_SHIFT 28 /* 128 MB */ -#define PREFETCH_FIFOTHRESHOLD (0x40 << 8) #define CS_NUM_SHIFT 24 #define ENABLE_PREFETCH (0x1 << 7) #define DMA_MPU_MODE 2 @@ -592,15 +591,19 @@ EXPORT_SYMBOL(gpmc_nand_write); /** * gpmc_prefetch_enable - configures and starts prefetch transfer * @cs: cs (chip select) number + * @fifo_th: fifo threshold to be used for read/ write * @dma_mode: dma mode enable (1) or disable (0) * @u32_count: number of bytes to be transferred * @is_write: prefetch read(0) or write post(1) mode */ -int gpmc_prefetch_enable(int cs, int dma_mode, +int gpmc_prefetch_enable(int cs, int fifo_th, int dma_mode, unsigned int u32_count, int is_write) { - if (!(gpmc_read_reg(GPMC_PREFETCH_CONTROL))) { + if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX) { + printk(KERN_ERR "PREFETCH Fifo Threshold is not supported\n"); + return -1; + } else if (!(gpmc_read_reg(GPMC_PREFETCH_CONTROL))) { /* Set the amount of bytes to be prefetched */ gpmc_write_reg(GPMC_PREFETCH_CONFIG2, u32_count); @@ -608,7 +611,7 @@ int gpmc_prefetch_enable(int cs, int dma_mode, * enable the engine. Set which cs is has requested for. */ gpmc_write_reg(GPMC_PREFETCH_CONFIG1, ((cs << CS_NUM_SHIFT) | - PREFETCH_FIFOTHRESHOLD | + PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH | (dma_mode << DMA_MPU_MODE) | (0x1 & is_write))); diff --git a/arch/arm/plat-omap/include/plat/gpmc.h b/arch/arm/plat-omap/include/plat/gpmc.h index 054e704..fb82335 100644 --- a/arch/arm/plat-omap/include/plat/gpmc.h +++ b/arch/arm/plat-omap/include/plat/gpmc.h @@ -83,6 +83,9 @@ #define GPMC_IRQ_FIFOEVENTENABLE 0x01 #define GPMC_IRQ_COUNT_EVENT 0x02 +#define PREFETCH_FIFOTHRESHOLD_MAX 0x40 +#define PREFETCH_FIFOTHRESHOLD(val) (val << 8) + /* * Note that all values in this struct are in nanoseconds, while * the register values are in gpmc_fck cycles. @@ -133,7 +136,7 @@ extern int gpmc_cs_request(int cs, unsigned long size, unsigned long *base); extern void gpmc_cs_free(int cs); extern int gpmc_cs_set_reserved(int cs, int reserved); extern int gpmc_cs_reserved(int cs); -extern int gpmc_prefetch_enable(int cs, int dma_mode, +extern int gpmc_prefetch_enable(int cs, int fifo_th, int dma_mode, unsigned int u32_count, int is_write); extern int gpmc_prefetch_reset(int cs); extern void omap3_gpmc_save_context(void); diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 9dc5ff9..20e73bf 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -275,7 +275,8 @@ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len) } /* configure and start prefetch transfer */ - ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x0); + ret = gpmc_prefetch_enable(info->gpmc_cs, + PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0); if (ret) { /* PFPW engine is busy, use cpu copy method */ if (info->nand.options & NAND_BUSWIDTH_16) @@ -319,7 +320,8 @@ static void omap_write_buf_pref(struct mtd_info *mtd, } /* configure and start prefetch transfer */ - ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x1); + ret = gpmc_prefetch_enable(info->gpmc_cs, + PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1); if (ret) { /* PFPW engine is busy, use cpu copy method */ if (info->nand.options & NAND_BUSWIDTH_16) @@ -373,10 +375,11 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, dma_addr_t dma_addr; int ret; - /* The fifo depth is 64 bytes. We have a sync at each frame and frame - * length is 64 bytes. + /* The fifo depth is 64 bytes max. + * But configure the FIFO-threahold to 32 to get a sync at each frame + * and frame length is 32 bytes. */ - int buf_len = len >> 6; + int buf_len = len >> 5; if (addr >= high_memory) { struct page *p1; @@ -415,7 +418,8 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, OMAP24XX_DMA_GPMC, OMAP_DMA_SRC_SYNC); } /* configure and start prefetch transfer */ - ret = gpmc_prefetch_enable(info->gpmc_cs, 0x1, len, is_write); + ret = gpmc_prefetch_enable(info->gpmc_cs, + PREFETCH_FIFOTHRESHOLD_MAX/2, 0x1, len, is_write); if (ret) /* PFPW engine is busy, use cpu copy methode */ goto out_copy; @@ -558,7 +562,8 @@ static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len) init_completion(&info->comp); /* configure and start prefetch transfer */ - ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x0); + ret = gpmc_prefetch_enable(info->gpmc_cs, + PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0); if (ret) /* PFPW engine is busy, use cpu copy methode */ goto out_copy; @@ -603,8 +608,9 @@ static void omap_write_buf_irq_pref(struct mtd_info *mtd, info->buf = (u_char *) buf; init_completion(&info->comp); - /* configure and start prefetch transfer */ - ret = gpmc_prefetch_enable(info->gpmc_cs, 0x0, len, 0x1); + /* configure and start prefetch transfer : size=24 */ + ret = gpmc_prefetch_enable(info->gpmc_cs, + (PREFETCH_FIFOTHRESHOLD_MAX*3)/8, 0x0, len, 0x1); if (ret) /* PFPW engine is busy, use cpu copy methode */ goto out_copy;