[PATCH v2 3/4] mtd:spi-nor:fsl-quadspi:Add fast-read mode support
From: Yunhui Cui <hidden>
Date: 2016-02-25 09:40:40
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Hi Han,
I have provided the options " m25p,fast-read ", because there are probable some flashes can't support quad mode.
So we should support fast-read mode in our driver. Moreover, There is a option to select fast-read mode in spi_nor.c :
/* If we were instantiated by DT, use it */
if (of_property_read_bool(np, "m25p,fast-read"))
nor->flash_read = SPI_NOR_FAST;
Thanks
Yunhui
-----Original Message-----
From: Han Xu [mailto:xhnjupt at gmail.com]
Sent: Thursday, February 18, 2016 2:08 AM
To: Yunhui Cui
Cc: dwmw2 at infradead.org; computersforpeace at gmail.com; han.xu at freescale.com; linux-mtd at lists.infradead.org; linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org; Yao Yuan
Subject: Re: [PATCH v2 3/4] mtd:spi-nor:fsl-quadspi:Add fast-read mode support
On Mon, Feb 01, 2016 at 07:30:07PM +0800, Yunhui Cui wrote:quoted hunk ↗ jump to hunk
The qspi driver add generic fast-read mode for different flash venders. There are some different board flash work on different mode, such fast-read, quad-mode. So we have to modify the third entrace parameter of spi_nor_scan(). Signed-off-by: Yunhui Cui <redacted> --- drivers/mtd/spi-nor/fsl-quadspi.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-)diff --git a/drivers/mtd/spi-nor/fsl-quadspi.cb/drivers/mtd/spi-nor/fsl-quadspi.c index 9861290..0a31cb1 100644--- a/drivers/mtd/spi-nor/fsl-quadspi.c +++ b/drivers/mtd/spi-nor/fsl-quadspi.c@@ -389,11 +389,21 @@ static void fsl_qspi_init_lut(struct fsl_qspi *q) /* Read */ lut_base = SEQID_READ * 4; - qspi_writel(q, LUT0(CMD, PAD1, read_op) | LUT1(ADDR, PAD1, addrlen), - base + QUADSPI_LUT(lut_base)); - qspi_writel(q, LUT0(DUMMY, PAD1, read_dm) | - LUT1(FSL_READ, PAD4, rxfifo), - base + QUADSPI_LUT(lut_base + 1)); + if (nor->flash_read == SPI_NOR_FAST) { + qspi_writel(q, LUT0(CMD, PAD1, read_op) | + LUT1(ADDR, PAD1, addrlen), + base + QUADSPI_LUT(lut_base)); + qspi_writel(q, LUT0(DUMMY, PAD1, read_dm) | + LUT1(FSL_READ, PAD1, rxfifo), + base + QUADSPI_LUT(lut_base + 1)); + } else if (nor->flash_read == SPI_NOR_QUAD) { + qspi_writel(q, LUT0(CMD, PAD1, read_op) | + LUT1(ADDR, PAD1, addrlen), + base + QUADSPI_LUT(lut_base)); + qspi_writel(q, LUT0(DUMMY, PAD1, read_dm) | + LUT1(FSL_READ, PAD4, rxfifo), + base + QUADSPI_LUT(lut_base + 1)); + } /* Write enable */ lut_base = SEQID_WREN * 4;@@ -468,6 +478,7 @@ static int fsl_qspi_get_seqid(struct fsl_qspi *q,u8 cmd) { switch (cmd) { case SPINOR_OP_READ_1_1_4: + case SPINOR_OP_READ_FAST: return SEQID_READ; case SPINOR_OP_WREN: return SEQID_WREN;@@ -963,6 +974,7 @@ static int fsl_qspi_probe(struct platform_device *pdev) struct spi_nor *nor; struct mtd_info *mtd; int ret, i = 0; + enum read_mode mode = SPI_NOR_QUAD; q = devm_kzalloc(dev, sizeof(*q), GFP_KERNEL); if (!q)@@ -1064,7 +1076,10 @@ static int fsl_qspi_probe(struct platform_device *pdev) /* set the chip address for READID */ fsl_qspi_set_base_addr(q, nor); - ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD); + ret = of_property_read_bool(np, "m25p,fast-read"); + mode = (ret) ? SPI_NOR_FAST : SPI_NOR_QUAD; + + ret = spi_nor_scan(nor, NULL, mode); if (ret) goto mutex_failed;
I understand you want to provide a more generic read mode, but this is a quad spi driver, I prefer to provide the options, either quad read/quad IO read, or just normal read.
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