Hi Bayi, (I drafted most of this before you clarified on how to read out 6 bytes of ID. So a bit of this is slightly out-of-date. Still, I think most of the comments and much of the appended patch should be useful to you.) On Mon, Oct 26, 2015 at 09:40:38PM +0800, Bayi Cheng wrote: > add spi nor flash driver for mediatek controller > > Signed-off-by: Bayi Cheng <bayi.cheng@xxxxxxxxxxxx> > --- > drivers/mtd/spi-nor/Kconfig | 7 + > drivers/mtd/spi-nor/Makefile | 1 + > drivers/mtd/spi-nor/mtk-quadspi.c | 491 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 499 insertions(+) > create mode 100644 drivers/mtd/spi-nor/mtk-quadspi.c > > diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig > index 89bf4c1..387396d 100644 > --- a/drivers/mtd/spi-nor/Kconfig > +++ b/drivers/mtd/spi-nor/Kconfig > @@ -7,6 +7,13 @@ menuconfig MTD_SPI_NOR > > if MTD_SPI_NOR > > +config MTD_MT81xx_NOR > + tristate "Mediatek MT81xx SPI NOR flash controller" > + help > + This enables access to SPI NOR flash, using MT81xx SPI NOR flash > + controller. This controller does not support generic SPI BUS, It only Nit: s/It/it/ > + supports SPI NOR Flash. > + > config MTD_SPI_NOR_USE_4K_SECTORS > bool "Use small 4096 B erase sectors" > default y > diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile > index e53333e..0bf3a7f8 100644 > --- a/drivers/mtd/spi-nor/Makefile > +++ b/drivers/mtd/spi-nor/Makefile > @@ -1,3 +1,4 @@ > obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o > obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o > +obj-$(CONFIG_MTD_MT81xx_NOR) += mtk-quadspi.o > obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o > diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c > new file mode 100644 > index 0000000..33a8dc5 > --- /dev/null > +++ b/drivers/mtd/spi-nor/mtk-quadspi.c > @@ -0,0 +1,491 @@ > +/* > + * Copyright (c) 2015 MediaTek Inc. > + * Author: Bayi Cheng <bayi.cheng@xxxxxxxxxxxx> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/device.h> > +#include <linux/init.h> > +#include <linux/io.h> > +#include <linux/iopoll.h> > +#include <linux/ioport.h> > +#include <linux/math64.h> > +#include <linux/module.h> > +#include <linux/mtd/mtd.h> > +#include <linux/mutex.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > +#include <linux/of_gpio.h> You're not using GPIOs. You don't need this header. > +#include <linux/pinctrl/consumer.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/mtd/mtd.h> > +#include <linux/mtd/partitions.h> > +#include <linux/mtd/spi-nor.h> > + > +#define MTK_NOR_CMD_REG 0x00 > +#define MTK_NOR_CNT_REG 0x04 > +#define MTK_NOR_RDSR_REG 0x08 > +#define MTK_NOR_RDATA_REG 0x0c > +#define MTK_NOR_RADR0_REG 0x10 > +#define MTK_NOR_RADR1_REG 0x14 > +#define MTK_NOR_RADR2_REG 0x18 > +#define MTK_NOR_WDATA_REG 0x1c > +#define MTK_NOR_PRGDATA0_REG 0x20 > +#define MTK_NOR_PRGDATA1_REG 0x24 > +#define MTK_NOR_PRGDATA2_REG 0x28 > +#define MTK_NOR_PRGDATA3_REG 0x2c > +#define MTK_NOR_PRGDATA4_REG 0x30 > +#define MTK_NOR_PRGDATA5_REG 0x34 > +#define MTK_NOR_SHREG0_REG 0x38 > +#define MTK_NOR_SHREG1_REG 0x3c > +#define MTK_NOR_SHREG2_REG 0x40 > +#define MTK_NOR_SHREG3_REG 0x44 > +#define MTK_NOR_SHREG4_REG 0x48 > +#define MTK_NOR_SHREG5_REG 0x4c > +#define MTK_NOR_SHREG6_REG 0x50 > +#define MTK_NOR_SHREG7_REG 0x54 > +#define MTK_NOR_SHREG8_REG 0x58 > +#define MTK_NOR_SHREG9_REG 0x5c > +#define MTK_NOR_CFG1_REG 0x60 > +#define MTK_NOR_CFG2_REG 0x64 > +#define MTK_NOR_CFG3_REG 0x68 > +#define MTK_NOR_STATUS0_REG 0x70 > +#define MTK_NOR_STATUS1_REG 0x74 > +#define MTK_NOR_STATUS2_REG 0x78 > +#define MTK_NOR_STATUS3_REG 0x7c > +#define MTK_NOR_FLHCFG_REG 0x84 > +#define MTK_NOR_TIME_REG 0x94 > +#define MTK_NOR_PP_DATA_REG 0x98 > +#define MTK_NOR_PREBUF_STUS_REG 0x9c > +#define MTK_NOR_DELSEL0_REG 0xa0 > +#define MTK_NOR_DELSEL1_REG 0xa4 > +#define MTK_NOR_INTRSTUS_REG 0xa8 > +#define MTK_NOR_INTREN_REG 0xac > +#define MTK_NOR_CHKSUM_CTL_REG 0xb8 > +#define MTK_NOR_CHKSUM_REG 0xbc > +#define MTK_NOR_CMD2_REG 0xc0 > +#define MTK_NOR_WRPROT_REG 0xc4 > +#define MTK_NOR_RADR3_REG 0xc8 > +#define MTK_NOR_DUAL_REG 0xcc > +#define MTK_NOR_DELSEL2_REG 0xd0 > +#define MTK_NOR_DELSEL3_REG 0xd4 > +#define MTK_NOR_DELSEL4_REG 0xd8 > + > +/* commands for mtk nor controller */ > +#define MTK_NOR_READ_CMD 0x0 > +#define MTK_NOR_RDSR_CMD 0x2 > +#define MTK_NOR_PRG_CMD 0x4 > +#define MTK_NOR_WR_CMD 0x10 > +#define MTK_NOR_PIO_WR_CMD 0x90 > +#define MTK_NOR_WRSR_CMD 0x20 > +#define MTK_NOR_PIO_READ_CMD 0x81 > +#define MTK_NOR_WR_BUF_ENABLE 0x1 > +#define MTK_NOR_WR_BUF_DISABLE 0x0 > +#define MTK_NOR_ENABLE_SF_CMD 0x30 > +#define MTK_NOR_DUAD_ADDR_EN 0x8 > +#define MTK_NOR_QUAD_READ_EN 0x4 > +#define MTK_NOR_DUAL_ADDR_EN 0x2 > +#define MTK_NOR_DUAL_READ_EN 0x1 > +#define MTK_NOR_DUAL_DISABLE 0x0 > +#define MTK_NOR_FAST_READ 0x1 > + > +#define SFLASH_WRBUF_SIZE 128 > +#define get_nth_byte(d, n) ((d >> (8 * n)) & 0xff) > + > +struct mt8173_nor { > + struct spi_nor nor; > + struct device *dev; > + void __iomem *base; /* nor flash base address */ > + struct clk *spi_clk; > + struct clk *nor_clk; > +}; > + > +static void mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor) > +{ > + struct spi_nor *nor = &mt8173_nor->nor; > + > + writeb(nor->read_opcode, mt8173_nor->base + MTK_NOR_PRGDATA3_REG); > + > + switch (nor->flash_read) { > + case SPI_NOR_FAST: > + writeb(MTK_NOR_FAST_READ, mt8173_nor->base + > + MTK_NOR_CFG1_REG); > + break; > + case SPI_NOR_DUAL: > + writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base + > + MTK_NOR_DUAL_REG); > + break; > + case SPI_NOR_QUAD: > + writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base + > + MTK_NOR_DUAL_REG); > + break; > + default: > + writeb(MTK_NOR_DUAL_DISABLE, mt8173_nor->base + > + MTK_NOR_DUAL_REG); > + break; > + } > +} > + > +static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval) > +{ > + int reg; > + u8 val = cmdval & 0x1f; > + > + writeb(cmdval, mt8173_nor->base + MTK_NOR_CMD_REG); > + return readl_poll_timeout(mt8173_nor->base + MTK_NOR_CMD_REG, reg, > + !(reg & val), 100, 10000); > +} > + > +static int mt8173_nor_do_tx(struct mt8173_nor *mt8173_nor, u8 op, u8 *buf, > + int len) I realized this code should probably be shared with some of the "read register" path too, so I'd suggest you make this a combined "tx_rx" function. I've written and tested a version myself, and I'll paste the (large) diff against your driver at the end of this email. > +{ > + int i; > + > + if (len > 5) > + return -EINVAL; > + > + writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); > + > + for (i = 0; i < len; i++) > + writeb(buf[len - 1 - i], mt8173_nor->base + I'm pretty sure this is wrong. You don't want to iterate over buf[] *and* PRGDATAx registers backwards; you want to both in the same direction. e.g.: buf[4] => PRGDATA0 buf[3] => PRGDATA1 buf[2] => PRGDATA2 ... or vice versa. I think this shows a bug in your address calculations for the erase command, and you "fixed" it by reversing the loop here. More below. > + MTK_NOR_PRGDATA0_REG + 4 * (4 - i)); > + writeb((len + 1) * 8, mt8173_nor->base + MTK_NOR_CNT_REG); > + return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD); If you extend this function to (optionall) read from SHREGx after the execute_cmd(), then you could share more code. > +} > + > +/* > + * this function is used to execute special read commands. > + * such as SPINOR_OP_RDFSR, SPINOR_OP_RDCR, SPINOR_OP_RD_EVCR and so on. > + * len is no more than 1. > + */ > +static int mt8173_nor_do_rx(struct mt8173_nor *mt8173_nor, u8 op, u8 *buf, > + int len) This is not a "do_rx" command; it doesn't even use the buf or len fields. > +{ > + if (len > 1) > + return -EINVAL; This should definitely be able to handle more than 1 byte. > + > + writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); > + > + writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG); > + return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD); > +} > + > +/* cmd1 sent to nor flash, cmd2 write to nor controller */ > +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1, > + int cmd2) This function will only actually be needed for the WRSR (write status register) command, so I'd restructure it / rename it. Again, see my patch below. > +{ > + writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); > + writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG); > + return mt8173_nor_execute_cmd(mt8173_nor, cmd2); > +} > + > +static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_nor) > +{ > + u8 reg; > + > + /* the bit0 of MTK_NOR_CFG2_REG is pre-fetch buffer > + * 0: pre-fetch buffer use for read > + * 1: pre-fetch buffer use for page program > + */ > + writel(MTK_NOR_WR_BUF_ENABLE, mt8173_nor->base + MTK_NOR_CFG2_REG); > + return readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg, > + 0x01 == (reg & 0x01), 100, 10000); > +} > + > +static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor) > +{ > + u8 reg; > + > + writel(MTK_NOR_WR_BUF_DISABLE, mt8173_nor->base + MTK_NOR_CFG2_REG); > + return readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg, > + MTK_NOR_WR_BUF_DISABLE == (reg & 0x1), 100, > + 10000); > +} > + > +static int mt8173_nor_erase_sector(struct spi_nor *nor, loff_t offset) > +{ > + u8 buf[4], i = 0; > + struct mt8173_nor *mt8173_nor = nor->priv; > + > + while (i < 4) { > + buf[i] = get_nth_byte(offset, i); > + i++; > + } This loop is wrong. Address bytes should not be sent in little endian order; the *highest* byte should be first. That's why your do_tx() function is all wrong. > + if (nor->mtd.size <= 0x1000000) > + return mt8173_nor_do_tx(mt8173_nor, SPINOR_OP_BE_4K, buf, 3); > + else > + return mt8173_nor_do_tx(mt8173_nor, SPINOR_OP_BE_4K, buf, 4); You've ignored some of my comments... do not hardcode the 4K sector command, because spi-nor could be using something else. You should use 'nor->erase_opcode'. Also, 4 vs. 3 should just be using 'nor->addr_width'. But this can be even easier: I noticed that you really are just open-coding a write_reg() call, just like m25p80.c was. So I refactored the code there and shared it in spi-nor for you [1]. With that patch, I don't think you'll even need to provide an erase() callback at all. Just use the default. > +} > + > +static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t length, > + size_t *retlen, u_char *buffer) > +{ > + int i, ret; > + int addr = (int)from; > + u8 *buf = (u8 *)buffer; > + struct mt8173_nor *mt8173_nor = nor->priv; > + > + /* set mode for fast read mode ,dual mode or quad mode */ > + mt8173_nor_set_read_mode(mt8173_nor); > + writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); > + writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); > + writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); > + writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); Programming the address registers is repeated in several places. Make that into a helper function. > + > + for (i = 0; i < length; i++, (*retlen)++) { > + ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD); > + if (ret < 0) > + return ret; > + buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG); > + } > + return 0; > +} > + > +static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor, > + int addr, int length, u8 *data) > +{ > + int i, ret; > + > + writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); > + writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); > + writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); > + writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); Helper function. > + > + for (i = 0; i < length; i++) { > + ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_WR_CMD); > + if (ret < 0) > + return ret; > + writeb(*data++, mt8173_nor->base + MTK_NOR_WDATA_REG); > + } > + return 0; > +} > + > +static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int addr, > + const u8 *buf) > +{ > + int i, bufidx, data; > + > + writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); > + writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); > + writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); > + writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); Helper function. > + > + bufidx = 0; > + for (i = 0; i < SFLASH_WRBUF_SIZE; i += 4) { > + data = buf[bufidx + 3]<<24 | buf[bufidx + 2]<<16 | > + buf[bufidx + 1]<<8 | buf[bufidx]; > + bufidx += 4; > + writel(data, mt8173_nor->base + MTK_NOR_PP_DATA_REG); > + } > + return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD); > +} > + > +static void mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len, > + size_t *retlen, const u_char *buf) > +{ > + int ret; > + struct mt8173_nor *mt8173_nor = nor->priv; > + > + ret = mt8173_nor_write_buffer_enable(mt8173_nor); > + if (ret < 0) > + dev_warn(mt8173_nor->dev, "write buffer enable failed!\n"); > + > + while (len >= SFLASH_WRBUF_SIZE) { > + ret = mt8173_nor_write_buffer(mt8173_nor, to, buf); > + if (ret < 0) > + dev_err(mt8173_nor->dev, "write buffer failed!\n"); > + len -= SFLASH_WRBUF_SIZE; > + to += SFLASH_WRBUF_SIZE; > + buf += SFLASH_WRBUF_SIZE; > + (*retlen) += SFLASH_WRBUF_SIZE; > + } > + ret = mt8173_nor_write_buffer_disable(mt8173_nor); > + if (ret < 0) > + dev_warn(mt8173_nor->dev, "write buffer disable failed!\n"); > + > + if (len) { > + ret = mt8173_nor_write_single_byte(mt8173_nor, to, (int)len, > + (u8 *)buf); > + if (ret < 0) > + dev_err(mt8173_nor->dev, "write single byte failed!\n"); > + (*retlen) += len; > + } > +} > + > +static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) > +{ > + int ret; > + struct mt8173_nor *mt8173_nor = nor->priv; > + > + /* mtk nor controller doesn't supoort SPINOR_OP_RDCR */ What's this comment about? I think your 'default' case below should handle that, right? > + switch (opcode) { > + case SPINOR_OP_RDID: > + /* read JEDEC ID need 4 bytes commands */ > + memset(buf, 0x0, 4); > + ret = mt8173_nor_do_tx(mt8173_nor, opcode, buf, 3); You should not be doing a "tx" here ("tx" meaning "transmit" [2] and "rx" meaning "receive"), because read ID is a "read" function. What your doing here is kind of hacky. Instead, you should have a better "do_rx" function (or, as I'm figuring out) a "do_tx_rx" function that can handle both cases in straightforward, logical code. See my patch below. > + if (ret < 0) > + return ret; > + > + /* mtk nor flash controller only support 3 bytes IDs */ > + buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG); > + buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG); > + buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG); As we discussed, you can support 5 bytes, not just 3. Now, we'll have to figure out for sure what to do about the remaining byte(s) that spi-nor.c wants (right now, it requests only 1 more). When hacking around myself, I figured if we see a RDID command of more than 5 bytes, we can just zero out the last byte(s) and run do_rx() with len==5. > + break; > + case SPINOR_OP_RDSR: > + ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD); > + if (ret < 0) > + return ret; > + *buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG); The caller asked for 'len' bytes. Usually that's 1, but we should be safe and check for 'len == 1'. > + break; > + default: > + /* read other register of nor flash */ > + ret = mt8173_nor_do_rx(mt8173_nor, opcode, buf, len); > + *buf = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG); The caller asked for 'len' bytes, so why are you only reading 1? > + break; > + } > + return ret; > +} > + > +static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, > + int len) > +{ > + int ret; > + struct mt8173_nor *mt8173_nor = nor->priv; > + > + switch (opcode) { > + case SPINOR_OP_WRSR: > + ret = mt8173_nor_set_para(mt8173_nor, *buf, > + MTK_NOR_WRSR_CMD); > + break; > + case SPINOR_OP_CHIP_ERASE: > + ret = mt8173_nor_set_para(mt8173_nor, opcode, > + MTK_NOR_PRG_CMD); This case should be able to fall under the default case. (If your do_tx() function actually worked right.) > + break; > + default: > + ret = mt8173_nor_do_tx(mt8173_nor, opcode, NULL, 0); Why are you passing NULL and 0?? That should be buf and len. > + if (ret) > + dev_warn(mt8173_nor->dev, "set write enable fail!\n"); > + break; > + } > + return ret; > +} > + > +static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor, > + struct mtd_part_parser_data *ppdata) > +{ > + int ret; > + struct spi_nor *nor; > + > + writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG); This deserves a comment about what it does. > + > + nor = &mt8173_nor->nor; > + nor->dev = mt8173_nor->dev; > + nor->priv = mt8173_nor; > + nor->flash_node = ppdata->of_node; > + > + /* fill the hooks to spi nor */ > + nor->read = mt8173_nor_read; > + nor->read_reg = mt8173_nor_read_reg; > + nor->write = mt8173_nor_write; > + nor->write_reg = mt8173_nor_write_reg; > + nor->erase = mt8173_nor_erase_sector; > + nor->mtd.owner = THIS_MODULE; > + nor->mtd.name = "mtk_nor"; > + /* initialized with NULL */ > + ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL); > + if (ret) > + return ret; > + > + return mtd_device_parse_register(&nor->mtd, NULL, ppdata, NULL, 0); > +} > + > +static int mtk_nor_drv_probe(struct platform_device *pdev) > +{ > + struct device_node *flash_np; > + struct mtd_part_parser_data ppdata; You never initialize this struct. So the other field(s) might contain garbage. > + struct resource *res; > + int ret; > + struct mt8173_nor *mt8173_nor; > + > + if (!pdev->dev.of_node) { > + dev_err(&pdev->dev, "No DT found\n"); > + return -EINVAL; > + } > + > + mt8173_nor = devm_kzalloc(&pdev->dev, sizeof(*mt8173_nor), GFP_KERNEL); > + if (!mt8173_nor) > + return -ENOMEM; > + platform_set_drvdata(pdev, mt8173_nor); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(mt8173_nor->base)) > + return PTR_ERR(mt8173_nor->base); > + > + mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi"); > + if (IS_ERR(mt8173_nor->spi_clk)) { > + ret = PTR_ERR(mt8173_nor->spi_clk); > + goto nor_free; > + } > + > + mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf"); > + if (IS_ERR(mt8173_nor->nor_clk)) { > + ret = PTR_ERR(mt8173_nor->nor_clk); > + goto nor_free; > + } > + > + mt8173_nor->dev = &pdev->dev; > + clk_prepare_enable(mt8173_nor->spi_clk); > + clk_prepare_enable(mt8173_nor->nor_clk); > + > + flash_np = of_get_next_available_child(pdev->dev.of_node, NULL); > + if (!flash_np) { > + dev_err(&pdev->dev, "no SPI flash device to configure\n"); > + ret = -ENODEV; > + goto nor_free; > + } > + ppdata.of_node = flash_np; > + ret = mtk_nor_init(mt8173_nor, &ppdata); > + > +nor_free: > + return ret; > +} > + > +static int mtk_nor_drv_remove(struct platform_device *pdev) > +{ > + struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev); > + > + clk_disable_unprepare(mt8173_nor->spi_clk); > + clk_disable_unprepare(mt8173_nor->nor_clk); > + return 0; > +} > + > +static const struct of_device_id mtk_nor_of_ids[] = { > + { .compatible = "mediatek,mt8173-nor"}, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, mtk_nor_of_ids); > + > +static struct platform_driver mtk_nor_driver = { > + .probe = mtk_nor_drv_probe, > + .remove = mtk_nor_drv_remove, > + .driver = { > + .name = "mtk-nor", > + .of_match_table = mtk_nor_of_ids, > + }, > +}; > + > +module_platform_driver(mtk_nor_driver); > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("MediaTek SPI NOR Flash Driver"); I will paste a big diff below. If you'd like, I can just email you the whole driver, since I redid significant portions of it. I tested all of it, and all the basic functions seem to work well. Brian [1] http://lists.infradead.org/pipermail/linux-mtd/2015-October/062916.html [2] https://en.wikipedia.org/wiki/Transmission_(telecommunications) --- diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c index 33a8dc56c20f..70dd62c7f989 100644 --- a/drivers/mtd/spi-nor/mtk-quadspi.c +++ b/drivers/mtd/spi-nor/mtk-quadspi.c @@ -101,7 +101,12 @@ #define MTK_NOR_FAST_READ 0x1 #define SFLASH_WRBUF_SIZE 128 -#define get_nth_byte(d, n) ((d >> (8 * n)) & 0xff) + +/* Can shift up to 48 bits (6 bytes) of TX/RX */ +#define MTK_NOR_MAX_SHIFT 6 +/* Helpers for accessing the program data / shift data registers */ +#define MTK_NOR_PRG_REG(n) (MTK_NOR_PRGDATA0_REG + 4 * (n)) +#define MTK_NOR_SHREG(n) (MTK_NOR_SHREG0_REG + 4 * (n)) struct mt8173_nor { struct spi_nor nor; @@ -147,47 +152,54 @@ static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval) !(reg & val), 100, 10000); } -static int mt8173_nor_do_tx(struct mt8173_nor *mt8173_nor, u8 op, u8 *buf, - int len) +static int mt8173_nor_do_tx_rx(struct mt8173_nor *mt8173_nor, u8 op, + u8 *tx, int txlen, u8 *rx, int rxlen) { - int i; + int len = 1 + txlen + rxlen; + int i, ret, idx; - if (len > 5) + if (len > MTK_NOR_MAX_SHIFT) return -EINVAL; - writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); + writeb(len * 8, mt8173_nor->base + MTK_NOR_CNT_REG); - for (i = 0; i < len; i++) - writeb(buf[len - 1 - i], mt8173_nor->base + - MTK_NOR_PRGDATA0_REG + 4 * (4 - i)); - writeb((len + 1) * 8, mt8173_nor->base + MTK_NOR_CNT_REG); - return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD); -} + /* start at PRGDATA5, go down to PRGDATA0 */ + idx = MTK_NOR_MAX_SHIFT - 1; -/* - * this function is used to execute special read commands. - * such as SPINOR_OP_RDFSR, SPINOR_OP_RDCR, SPINOR_OP_RD_EVCR and so on. - * len is no more than 1. - */ -static int mt8173_nor_do_rx(struct mt8173_nor *mt8173_nor, u8 op, u8 *buf, - int len) -{ - if (len > 1) - return -EINVAL; + /* opcode */ + writeb(op, mt8173_nor->base + MTK_NOR_PRG_REG(idx)); + idx--; - writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); + /* program TX data */ + for (i = 0; i < txlen; i++, idx--) + writeb(tx[i], mt8173_nor->base + MTK_NOR_PRG_REG(idx)); - writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG); - return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD); + /* clear out rest of TX registers */ + while (idx >= 0) { + writeb(0, mt8173_nor->base + MTK_NOR_PRG_REG(idx)); + idx--; + } + + ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD); + if (ret) + return ret; + + /* restart at first RX byte */ + idx = MTK_NOR_MAX_SHIFT - 2 - txlen; + + /* read out RX data */ + for (i = 0; i < rxlen; i++, idx--) + rx[i] = readb(mt8173_nor->base + MTK_NOR_SHREG(idx)); + + return 0; } -/* cmd1 sent to nor flash, cmd2 write to nor controller */ -static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1, - int cmd2) +/* Do a WRSR (Write Status Register) command */ +static int mt8173_nor_wr_sr(struct mt8173_nor *mt8173_nor, u8 sr) { - writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); + writeb(sr, mt8173_nor->base + MTK_NOR_PRGDATA5_REG); writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG); - return mt8173_nor_execute_cmd(mt8173_nor, cmd2); + return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WRSR_CMD); } static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_nor) @@ -213,19 +225,16 @@ static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor) 10000); } -static int mt8173_nor_erase_sector(struct spi_nor *nor, loff_t offset) +static void mt8173_nor_set_addr(struct mt8173_nor *mt8173_nor, u32 addr) { - u8 buf[4], i = 0; - struct mt8173_nor *mt8173_nor = nor->priv; + int i; - while (i < 4) { - buf[i] = get_nth_byte(offset, i); - i++; + for (i = 0; i < 3; i++) { + writeb(addr & 0xff, mt8173_nor->base + MTK_NOR_RADR0_REG + i * 4); + addr >>= 8; } - if (nor->mtd.size <= 0x1000000) - return mt8173_nor_do_tx(mt8173_nor, SPINOR_OP_BE_4K, buf, 3); - else - return mt8173_nor_do_tx(mt8173_nor, SPINOR_OP_BE_4K, buf, 4); + /* Last register is non-contiguous */ + writeb(addr & 0xff, mt8173_nor->base + MTK_NOR_RADR3_REG); } static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t length, @@ -238,10 +247,7 @@ static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t length, /* set mode for fast read mode ,dual mode or quad mode */ mt8173_nor_set_read_mode(mt8173_nor); - writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); - writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); - writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); - writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); + mt8173_nor_set_addr(mt8173_nor, addr); for (i = 0; i < length; i++, (*retlen)++) { ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD); @@ -257,10 +263,7 @@ static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor, { int i, ret; - writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); - writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); - writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); - writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); + mt8173_nor_set_addr(mt8173_nor, addr); for (i = 0; i < length; i++) { ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_WR_CMD); @@ -276,10 +279,7 @@ static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int addr, { int i, bufidx, data; - writeb((addr >> 24), mt8173_nor->base + MTK_NOR_RADR3_REG); - writeb((addr >> 16), mt8173_nor->base + MTK_NOR_RADR2_REG); - writeb((addr >> 8), mt8173_nor->base + MTK_NOR_RADR1_REG); - writeb(addr, mt8173_nor->base + MTK_NOR_RADR0_REG); + mt8173_nor_set_addr(mt8173_nor, addr); bufidx = 0; for (i = 0; i < SFLASH_WRBUF_SIZE; i += 4) { @@ -330,28 +330,23 @@ static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) /* mtk nor controller doesn't supoort SPINOR_OP_RDCR */ switch (opcode) { - case SPINOR_OP_RDID: - /* read JEDEC ID need 4 bytes commands */ - memset(buf, 0x0, 4); - ret = mt8173_nor_do_tx(mt8173_nor, opcode, buf, 3); - if (ret < 0) - return ret; - - /* mtk nor flash controller only support 3 bytes IDs */ - buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG); - buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG); - buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG); - break; case SPINOR_OP_RDSR: ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD); if (ret < 0) return ret; *buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG); break; + case SPINOR_OP_RDID: + if (len > MTK_NOR_MAX_SHIFT - 1) { + int i; + /* HACK */ + for (i = MTK_NOR_MAX_SHIFT - 1; i < len; i++) + buf[i] = 0; + len = MTK_NOR_MAX_SHIFT - 1; + } + /* fall through */ default: - /* read other register of nor flash */ - ret = mt8173_nor_do_rx(mt8173_nor, opcode, buf, len); - *buf = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG); + ret = mt8173_nor_do_tx_rx(mt8173_nor, opcode, NULL, 0, buf, len); break; } return ret; @@ -365,41 +360,40 @@ static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, switch (opcode) { case SPINOR_OP_WRSR: - ret = mt8173_nor_set_para(mt8173_nor, *buf, - MTK_NOR_WRSR_CMD); - break; - case SPINOR_OP_CHIP_ERASE: - ret = mt8173_nor_set_para(mt8173_nor, opcode, - MTK_NOR_PRG_CMD); + /* We only handle 1 byte */ + ret = mt8173_nor_wr_sr(mt8173_nor, *buf); break; default: - ret = mt8173_nor_do_tx(mt8173_nor, opcode, NULL, 0); + ret = mt8173_nor_do_tx_rx(mt8173_nor, opcode, buf, len, NULL, 0); if (ret) - dev_warn(mt8173_nor->dev, "set write enable fail!\n"); + dev_warn(mt8173_nor->dev, "write reg failure!\n"); break; } return ret; } static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor, - struct mtd_part_parser_data *ppdata) + struct device_node *flash_node) { + struct mtd_part_parser_data ppdata = { + .of_node = flash_node, + }; int ret; struct spi_nor *nor; + /* initialize controller to accept commands */ writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG); nor = &mt8173_nor->nor; nor->dev = mt8173_nor->dev; nor->priv = mt8173_nor; - nor->flash_node = ppdata->of_node; + nor->flash_node = flash_node; /* fill the hooks to spi nor */ nor->read = mt8173_nor_read; nor->read_reg = mt8173_nor_read_reg; nor->write = mt8173_nor_write; nor->write_reg = mt8173_nor_write_reg; - nor->erase = mt8173_nor_erase_sector; nor->mtd.owner = THIS_MODULE; nor->mtd.name = "mtk_nor"; /* initialized with NULL */ @@ -407,13 +401,12 @@ static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor, if (ret) return ret; - return mtd_device_parse_register(&nor->mtd, NULL, ppdata, NULL, 0); + return mtd_device_parse_register(&nor->mtd, NULL, &ppdata, NULL, 0); } static int mtk_nor_drv_probe(struct platform_device *pdev) { struct device_node *flash_np; - struct mtd_part_parser_data ppdata; struct resource *res; int ret; struct mt8173_nor *mt8173_nor; @@ -449,14 +442,14 @@ static int mtk_nor_drv_probe(struct platform_device *pdev) clk_prepare_enable(mt8173_nor->spi_clk); clk_prepare_enable(mt8173_nor->nor_clk); + /* only support one attached flash */ flash_np = of_get_next_available_child(pdev->dev.of_node, NULL); if (!flash_np) { dev_err(&pdev->dev, "no SPI flash device to configure\n"); ret = -ENODEV; goto nor_free; } - ppdata.of_node = flash_np; - ret = mtk_nor_init(mt8173_nor, &ppdata); + ret = mtk_nor_init(mt8173_nor, flash_np); nor_free: return ret; -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html