Legacy mips soc platforms that have controller v5.0 and 6.0 use flash-edu block for dma transfers. This change adds support for nand dma transfers using the EDU block.

Signed-off-by: Kamal Dasu kdasu.kdev@gmail.com --- drivers/mtd/nand/raw/brcmnand/brcmnand.c | 296 ++++++++++++++++++++++- 1 file changed, 290 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c index 1a66b1cd51c0..61347607f1da 100644 --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c @@ -102,6 +102,45 @@ struct brcm_nand_dma_desc { #define NAND_CTRL_RDY (INTFC_CTLR_READY | INTFC_FLASH_READY) #define NAND_POLL_STATUS_TIMEOUT_MS 100

+#define EDU_CMD_WRITE 0x00 +#define EDU_CMD_READ 0x01 +#define EDU_STATUS_ACTIVE BIT(0) +#define EDU_ERR_STATUS_ERRACK BIT(0) +#define EDU_DONE_MASK GENMASK(1, 0) + +#define EDU_CONFIG_MODE_NAND BIT(0) +#define EDU_CONFIG_SWAP_BYTE BIT(1) +#ifdef CONFIG_CPU_BIG_ENDIAN +#define EDU_CONFIG_SWAP_CFG EDU_CONFIG_SWAP_BYTE +#else +#define EDU_CONFIG_SWAP_CFG 0 +#endif + +/* edu registers */ +enum edu_reg { + EDU_CONFIG = 0, + EDU_DRAM_ADDR, + EDU_EXT_ADDR, + EDU_LENGTH, + EDU_CMD, + EDU_STOP, + EDU_STATUS, + EDU_DONE, + EDU_ERR_STATUS, +}; + +static const u16 edu_regs[] = { + [EDU_CONFIG] = 0x00, + [EDU_DRAM_ADDR] = 0x04, + [EDU_EXT_ADDR] = 0x08, + [EDU_LENGTH] = 0x0c, + [EDU_CMD] = 0x10, + [EDU_STOP] = 0x14, + [EDU_STATUS] = 0x18, + [EDU_DONE] = 0x1c, + [EDU_ERR_STATUS] = 0x20, +}; + /* flash_dma registers */ enum flash_dma_reg { FLASH_DMA_REVISION = 0, @@ -167,6 +206,8 @@ enum { BRCMNAND_HAS_WP = BIT(3), };

+struct brcmnand_host; + struct brcmnand_controller { struct device *dev; struct nand_controller controller; @@ -185,17 +226,32 @@ struct brcmnand_controller {

int cmd_pending; bool dma_pending; + bool edu_pending; struct completion done; struct completion dma_done; + struct completion edu_done;

/* List of NAND hosts (one for each chip-select) */ struct list_head host_list;

+ /* EDU info, per-transaction */ + const u16 *edu_offsets; + void __iomem *edu_base; + unsigned int edu_irq; + int edu_count; + u64 edu_dram_addr; + u32 edu_ext_addr; + u32 edu_cmd; + u32 edu_config; + /* flash_dma reg */ const u16 *flash_dma_offsets; struct brcm_nand_dma_desc *dma_desc; dma_addr_t dma_pa;

+ int (*dma_trans)(struct brcmnand_host *host, u64 addr, u32 *buf, + u32 len, u8 dma_cmd); + /* in-memory cache of the FLASH_CACHE, used only for some commands */ u8 flash_cache[FC_BYTES];

@@ -216,6 +272,7 @@ struct brcmnand_controller { u32 nand_cs_nand_xor; u32 corr_stat_threshold; u32 flash_dma_mode; + u32 flash_edu_mode; bool pio_poll_mode; };

@@ -657,6 +714,22 @@ static inline void brcmnand_write_fc(struct brcmnand_controller *ctrl, __raw_writel(val, ctrl->nand_fc + word * 4); }

+static inline void edu_writel(struct brcmnand_controller *ctrl, + enum edu_reg reg, u32 val) +{ + u16 offs = ctrl->edu_offsets[reg]; + + brcmnand_writel(val, ctrl->edu_base + offs); +} + +static inline u32 edu_readl(struct brcmnand_controller *ctrl, + enum edu_reg reg) +{ + u16 offs = ctrl->edu_offsets[reg]; + + return brcmnand_readl(ctrl->edu_base + offs); +} + static void brcmnand_clear_ecc_addr(struct brcmnand_controller *ctrl) {

@@ -926,6 +999,16 @@ static inline bool has_flash_dma(struct brcmnand_controller *ctrl) return ctrl->flash_dma_base; }

+static inline bool has_edu(struct brcmnand_controller *ctrl) +{ + return ctrl->edu_base; +} + +static inline bool use_dma(struct brcmnand_controller *ctrl) +{ + return has_flash_dma(ctrl) || has_edu(ctrl); +} + static inline void disable_ctrl_irqs(struct brcmnand_controller *ctrl) { if (ctrl->pio_poll_mode) @@ -1299,6 +1382,52 @@ static int write_oob_to_regs(struct brcmnand_controller *ctrl, int i, return tbytes; }

+static void brcmnand_edu_init(struct brcmnand_controller *ctrl) +{ + /* initialize edu */ + edu_writel(ctrl, EDU_ERR_STATUS, 0); + edu_readl(ctrl, EDU_ERR_STATUS); + edu_writel(ctrl, EDU_DONE, 0); + edu_writel(ctrl, EDU_DONE, 0); + edu_writel(ctrl, EDU_DONE, 0); + edu_writel(ctrl, EDU_DONE, 0); + edu_readl(ctrl, EDU_DONE); +} + +/* edu irq */ +static irqreturn_t brcmnand_edu_irq(int irq, void *data) +{ + struct brcmnand_controller *ctrl = data; + + if (ctrl->edu_count) { + ctrl->edu_count--; + while (!(edu_readl(ctrl, EDU_DONE) & EDU_DONE_MASK)) + udelay(1); + edu_writel(ctrl, EDU_DONE, 0); + edu_readl(ctrl, EDU_DONE); + } + + if (ctrl->edu_count) { + ctrl->edu_dram_addr += FC_BYTES; + ctrl->edu_ext_addr += FC_BYTES; + + edu_writel(ctrl, EDU_DRAM_ADDR, (u32)ctrl->edu_dram_addr); + edu_readl(ctrl, EDU_DRAM_ADDR); + edu_writel(ctrl, EDU_EXT_ADDR, ctrl->edu_ext_addr); + edu_readl(ctrl, EDU_EXT_ADDR); + + mb(); /* flush previous writes */ + edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd); + edu_readl(ctrl, EDU_CMD); + + return IRQ_HANDLED; + } + + complete(&ctrl->edu_done); + + return IRQ_HANDLED; +} + static irqreturn_t brcmnand_ctlrdy_irq(int irq, void *data) { struct brcmnand_controller *ctrl = data; @@ -1307,6 +1436,16 @@ static irqreturn_t brcmnand_ctlrdy_irq(int irq, void *data) if (ctrl->dma_pending) return IRQ_HANDLED;

+ /* check if you need to piggy back on the ctrlrdy irq */ + if (ctrl->edu_pending) { + if (irq == ctrl->irq && ((int)ctrl->edu_irq >= 0)) + /* Discard interrupts while using dedicated edu irq */ + return IRQ_HANDLED; + + /* no registered edu irq, call handler */ + return brcmnand_edu_irq(irq, data); + } + complete(&ctrl->done); return IRQ_HANDLED; } @@ -1644,6 +1783,83 @@ static void brcmnand_write_buf(struct nand_chip *chip, const uint8_t *buf, } }

+/** + * Kick EDU engine + */ +static int brcmnand_edu_trans(struct brcmnand_host *host, u64 addr, u32 *buf, + u32 len, u8 cmd) +{ + struct brcmnand_controller *ctrl = host->ctrl; + unsigned long timeo = msecs_to_jiffies(200); + int ret = 0; + int dir = (cmd == CMD_PAGE_READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE); + u8 edu_cmd = (cmd == CMD_PAGE_READ ? EDU_CMD_READ : EDU_CMD_WRITE); + unsigned int trans = len >> FC_SHIFT; + dma_addr_t pa; + + pa = dma_map_single(ctrl->dev, buf, len, dir); + if (dma_mapping_error(ctrl->dev, pa)) { + dev_err(ctrl->dev, "unable to map buffer for EDU DMA\n"); + return -ENOMEM; + } + + ctrl->edu_pending = true; + mb(); /* flush previous writes */ + + ctrl->edu_dram_addr = pa; + ctrl->edu_ext_addr = addr; + ctrl->edu_cmd = edu_cmd; + ctrl->edu_count = trans; + + edu_writel(ctrl, EDU_DRAM_ADDR, (u32)ctrl->edu_dram_addr); + edu_readl(ctrl, EDU_DRAM_ADDR); + edu_writel(ctrl, EDU_EXT_ADDR, ctrl->edu_ext_addr); + edu_readl(ctrl, EDU_EXT_ADDR); + edu_writel(ctrl, EDU_LENGTH, FC_BYTES); + edu_readl(ctrl, EDU_LENGTH); + + /* Start edu engine */ + mb(); /* flush previous writes */ + edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd); + edu_readl(ctrl, EDU_CMD); + + if (wait_for_completion_timeout(&ctrl->edu_done, timeo) <= 0) { + dev_err(ctrl->dev, + "timeout waiting for EDU; status %#x, error status %#x\n", + edu_readl(ctrl, EDU_STATUS), + edu_readl(ctrl, EDU_ERR_STATUS)); + } + + dma_unmap_single(ctrl->dev, pa, len, dir); + + /* for program page check NAND status */ + if (((brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS) & + INTFC_FLASH_STATUS) & NAND_STATUS_FAIL) && + edu_cmd == EDU_CMD_WRITE) { + dev_info(ctrl->dev, "program failed at %llx\n", + (unsigned long long)addr); + ret = -EIO; + } + + /* Make sure the EDU status is clean */ + if (edu_readl(ctrl, EDU_STATUS) & EDU_STATUS_ACTIVE) + dev_warn(ctrl->dev, "EDU still active: %#x\n", + edu_readl(ctrl, EDU_STATUS)); + + if (unlikely(edu_readl(ctrl, EDU_ERR_STATUS) & EDU_ERR_STATUS_ERRACK)) { + dev_warn(ctrl->dev, "EDU RBUS error at addr %llx\n", + (unsigned long long)addr); + ret = -EIO; + } + + ctrl->edu_pending = false; + brcmnand_edu_init(ctrl); + edu_writel(ctrl, EDU_STOP, 0); /* force stop */ + edu_readl(ctrl, EDU_STOP); + + return ret; +} + /** * Construct a FLASH_DMA descriptor as part of a linked list. You must know the * following ahead of time: @@ -1850,9 +2066,11 @@ static int brcmnand_read(struct mtd_info *mtd, struct nand_chip *chip, try_dmaread: brcmnand_clear_ecc_addr(ctrl);

- if (has_flash_dma(ctrl) && !oob && flash_dma_buf_ok(buf)) { - err = brcmnand_dma_trans(host, addr, buf, trans * FC_BYTES, - CMD_PAGE_READ); + if (ctrl->dma_trans && !oob && flash_dma_buf_ok(buf)) { + err = ctrl->dma_trans(host, addr, buf, + trans * FC_BYTES, + CMD_PAGE_READ); + if (err) { if (mtd_is_bitflip_or_eccerr(err)) err_addr = addr; @@ -1988,10 +2206,12 @@ static int brcmnand_write(struct mtd_info *mtd, struct nand_chip *chip, for (i = 0; i < ctrl->max_oob; i += 4) oob_reg_write(ctrl, i, 0xffffffff);

- if (has_flash_dma(ctrl) && !oob && flash_dma_buf_ok(buf)) { - if (brcmnand_dma_trans(host, addr, (u32 *)buf, - mtd->writesize, CMD_PROGRAM_PAGE)) + if (use_dma(ctrl) && !oob && flash_dma_buf_ok(buf)) { + if (ctrl->dma_trans(host, addr, (u32 *)buf, mtd->writesize, + CMD_PROGRAM_PAGE)) + ret = -EIO; + goto out; }

@@ -2494,6 +2714,8 @@ static int brcmnand_suspend(struct device *dev)

if (has_flash_dma(ctrl)) ctrl->flash_dma_mode = flash_dma_readl(ctrl, FLASH_DMA_MODE); + else if (has_edu(ctrl)) + ctrl->edu_config = edu_readl(ctrl, EDU_CONFIG);

return 0; } @@ -2508,6 +2730,14 @@ static int brcmnand_resume(struct device *dev) flash_dma_writel(ctrl, FLASH_DMA_ERROR_STATUS, 0); }

+ if (has_edu(ctrl)) + ctrl->edu_config = edu_readl(ctrl, EDU_CONFIG); + else { + edu_writel(ctrl, EDU_CONFIG, ctrl->edu_config); + edu_readl(ctrl, EDU_CONFIG); + brcmnand_edu_init(ctrl); + } + brcmnand_write_reg(ctrl, BRCMNAND_CS_SELECT, ctrl->nand_cs_nand_select); brcmnand_write_reg(ctrl, BRCMNAND_CS_XOR, ctrl->nand_cs_nand_xor); brcmnand_write_reg(ctrl, BRCMNAND_CORR_THRESHOLD, @@ -2553,6 +2783,52 @@ MODULE_DEVICE_TABLE(of, brcmnand_of_match); /*********************************************************************** * Platform driver setup (per controller) ***********************************************************************/ +static int brcmnand_edu_setup(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct brcmnand_controller *ctrl = dev_get_drvdata(&pdev->dev); + struct resource *res; + int ret; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash-edu"); + if (res) { + ctrl->edu_base = devm_ioremap_resource(dev, res); + if (IS_ERR(ctrl->edu_base)) + return PTR_ERR(ctrl->edu_base); + + ctrl->edu_offsets = edu_regs; + + edu_writel(ctrl, EDU_CONFIG, EDU_CONFIG_MODE_NAND | + EDU_CONFIG_SWAP_CFG); + edu_readl(ctrl, EDU_CONFIG); + + /* initialize edu */ + brcmnand_edu_init(ctrl); + + ctrl->edu_irq = platform_get_irq_optional(pdev, 1); + if ((int)ctrl->edu_irq < 0) { + dev_warn(dev, + "FLASH EDU enabled, using ctlrdy irq\n"); + } else { + ret = devm_request_irq(dev, ctrl->edu_irq, + brcmnand_edu_irq, 0, + "brcmnand-edu", ctrl); + if (ret < 0) { + dev_err(ctrl->dev, "can't allocate IRQ %d: error %d\n", + ctrl->edu_irq, ret); + return ret; + } + + dev_info(dev, "FLASH EDU enabled using irq %u\n", + ctrl->edu_irq); + } + + /* set the appropriate edu transfer function to call */ + ctrl->dma_trans = brcmnand_edu_trans; + } + + return 0; +}

int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc) { @@ -2578,6 +2854,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)

init_completion(&ctrl->done); init_completion(&ctrl->dma_done); + init_completion(&ctrl->edu_done); nand_controller_init(&ctrl->controller); ctrl->controller.ops = &brcmnand_controller_ops; INIT_LIST_HEAD(&ctrl->host_list); @@ -2623,6 +2900,7 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc) ctrl->reg_offsets[BRCMNAND_FC_BASE]; }

+ ctrl->dma_trans = NULL; /* FLASH_DMA */ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash-dma"); if (res) { @@ -2665,6 +2943,12 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc) }

dev_info(dev, "enabling FLASH_DMA\n"); + /* set the appropriate flash dma transfer function to call */ + ctrl->dma_trans = brcmnand_dma_trans; + } else { + ret = brcmnand_edu_setup(pdev); + if (ret < 0) + goto err; }

/* Disable automatic device ID config, direct addressing */ -- 2.17.1