This patch enable prefetch-irq mode for NAND.
Signed-off-by: Vimal Singh <vimalsingh@xxxxxx>
Signed-off-by: Sukumar Ghorai <s-ghorai@xxxxxx>
---
arch/arm/mach-omap2/board-sdp-flash.c | 1 +
arch/arm/mach-omap2/board-zoom-flash.c | 1 +
arch/arm/plat-omap/include/plat/nand.h | 1 +
drivers/mtd/nand/Kconfig | 14 +++-
drivers/mtd/nand/omap2.c | 180 +++++++++++++++++++++++++++++++-
5 files changed, 191 insertions(+), 6 deletions(-)
diff --git a/arch/arm/mach-omap2/board-sdp-flash.c b/arch/arm/mach-omap2/board-sdp-flash.c
index 57116e6..81b83ce
--- a/arch/arm/mach-omap2/board-sdp-flash.c
+++ b/arch/arm/mach-omap2/board-sdp-flash.c
@@ -151,6 +151,7 @@ static struct omap_nand_platform_data sdp_nand_data = {
.nand_setup = NULL,
.gpmc_t = &nand_timings,
.dma_channel = -1, /* disable DMA in OMAP NAND driver */
+ .gpmc_irq = 20,
.dev_ready = NULL,
.devsize = 0, /* '0' for 8-bit, '1' for 16-bit device */
};
diff --git a/arch/arm/mach-omap2/board-zoom-flash.c b/arch/arm/mach-omap2/board-zoom-flash.c
index 55e173b..6a5dcf4 100644
--- a/arch/arm/mach-omap2/board-zoom-flash.c
+++ b/arch/arm/mach-omap2/board-zoom-flash.c
@@ -54,6 +54,7 @@ static struct omap_nand_platform_data zoom_nand_data = {
.nand_setup = NULL,
.gpmc_t = &nand_timings,
.dma_channel = -1, /* disable DMA in OMAP NAND driver */
+ .gpmc_irq = 20,
.dev_ready = NULL,
.devsize = 1, /* '0' for 8-bit, '1' for 16-bit device */
};
diff --git a/arch/arm/plat-omap/include/plat/nand.h b/arch/arm/plat-omap/include/plat/nand.h
index 6ba88d2..8ba2e3e 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;
void __iomem *gpmc_cs_baseaddr;
void __iomem *gpmc_baseaddr;
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index b712aed..ee9abbd
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -94,6 +94,9 @@ 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
@@ -102,7 +105,16 @@ 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 09a89f9..de9b058 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -11,6 +11,7 @@
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
+#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/mtd/mtd.h>
@@ -111,17 +112,27 @@ 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 {
@@ -139,6 +150,8 @@ struct omap_nand_info {
void __iomem *nand_pref_fifo_add;
struct completion comp;
int dma_ch;
+ int gpmc_irq;
+ u_char *buf;
};
/**
@@ -503,6 +516,141 @@ 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 irq_enb = 0, pref_status = 0, bytes = 0;
+ u32 irq_stats = __raw_readl(info->gpmc_baseaddr + GPMC_IRQSTATUS);
+ u32 pref_config = __raw_readl(info->gpmc_baseaddr +
+ GPMC_PREFETCH_CONFIG1);
+
+ if (pref_config & 0x1) { /* checks for write operaiton */
+ if (irq_stats & 0x2)
+ goto done;
+
+ u32 *p = (u32 *) info->buf;
+ pref_status = gpmc_prefetch_status();
+ bytes = ((pref_status >> 24) & 0x7F);
+ iowrite32_rep(info->nand_pref_fifo_add, p, bytes >> 2);
+ info->buf = info->buf + bytes;
+
+ } else {
+ u32 *p = (u32 *) info->buf;
+ pref_status = gpmc_prefetch_status();
+ bytes = ((pref_status >> 24) & 0x7F);
+ ioread32_rep(info->nand_pref_fifo_add, p, bytes >> 2);
+ info->buf = info->buf + bytes;
+
+ if (irq_stats & 0x2)
+ goto done;
+ }
+ __raw_writel(irq_stats, info->gpmc_baseaddr + GPMC_IRQSTATUS);
+ irq_stats = __raw_readl(info->gpmc_baseaddr + GPMC_IRQSTATUS);
+
+ return IRQ_HANDLED;
+
+done:
+ complete(&info->comp);
+ irq_enb = __raw_readl(info->gpmc_baseaddr + GPMC_IRQENABLE);
+ __raw_writel((irq_enb & ~0x3), info->gpmc_baseaddr + GPMC_IRQENABLE);
+ __raw_writel(irq_stats, info->gpmc_baseaddr + GPMC_IRQSTATUS);
+ irq_stats = __raw_readl(info->gpmc_baseaddr + GPMC_IRQSTATUS);
+
+ 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);
+ u32 irq_enb = __raw_readl(info->gpmc_baseaddr + GPMC_IRQENABLE);
+ int ret = 0;
+
+ if (len <= mtd->oobsize) {
+ omap_read_buf_pref(mtd, buf, len);
+ return;
+ }
+
+ 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;
+
+ __raw_writel((irq_enb | 0x3), info->gpmc_baseaddr + GPMC_IRQENABLE);
+
+ /* setup and start DMA using dma_addr */
+ wait_for_completion(&info->comp);
+
+ /* disable and stop the PFPW engine */
+ gpmc_prefetch_reset();
+
+ 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);
+ u32 irq_enb = __raw_readl(info->gpmc_baseaddr + GPMC_IRQENABLE);
+ int ret = 0;
+
+ if (len <= mtd->oobsize) {
+ omap_write_buf_pref(mtd, buf, len);
+ return;
+ }
+
+ 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;
+
+ __raw_writel((irq_enb | 0x3), info->gpmc_baseaddr + GPMC_IRQENABLE);
+
+ /* setup and start DMA using dma_addr */
+ wait_for_completion(&info->comp);
+
+ /* disable and stop the PFPW engine */
+ gpmc_prefetch_reset();
+
+ 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
@@ -898,6 +1046,7 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
info->gpmc_cs = pdata->cs;
info->gpmc_baseaddr = pdata->gpmc_baseaddr;
info->gpmc_cs_baseaddr = pdata->gpmc_cs_baseaddr;
+ info->gpmc_irq = pdata->gpmc_irq;
info->phys_base = pdata->phys_base;
info->mtd.priv = &info->nand;
@@ -964,7 +1113,20 @@ 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, info->mtd.name, info);
+ if (err) {
+ printk(KERN_INFO"failure requesting irq %i."
+ " Prefetch will work in mpu"
+ " poling mode.\n",
+ info->gpmc_irq);
+ } 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;
@@ -1056,11 +1218,19 @@ 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);
}
--
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