Adding support for EBI DMA unit (EDU).

Signed-off-by: Kamal Dasu kdasu.kdev@gmail.com Reviewed-by: Rob Herring robh@kernel.org --- .../devicetree/bindings/mtd/brcm,brcmnand.txt | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt index 82156dc8f304..05651a654c66 100644 --- a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt +++ b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt @@ -35,11 +35,11 @@ Required properties: (optional) NAND flash cache range (if at non-standard offset) - reg-names : a list of the names corresponding to the previous register ranges. Should contain "nand" and (optionally) - "flash-dma" and/or "nand-cache". -- interrupts : The NAND CTLRDY interrupt and (if Flash DMA is available) - FLASH_DMA_DONE -- interrupt-names : May be "nand_ctlrdy" or "flash_dma_done", if broken out as - individual interrupts. + "flash-dma" or "flash-edu" and/or "nand-cache". +- interrupts : The NAND CTLRDY interrupt, (if Flash DMA is available) + FLASH_DMA_DONE and if EDU is avaialble and used FLASH_EDU_DONE +- interrupt-names : May be "nand_ctlrdy" or "flash_dma_done" or "flash_edu_done", + if broken out as individual interrupts. May be "nand", if the SoC has the individual NAND interrupts multiplexed behind another custom piece of hardware

Nand controller v5.0 and v6.0 have nand edu blocks that enable dma nand flash transfers. This allows for faster read and write access.

Signed-off-by: Kamal Dasu kdasu.kdev@gmail.com Acked-by: Paul Burton paulburton@kernel.org Reviewed-by: Florian Fainelli f.fainelli@gmail.com --- arch/mips/boot/dts/brcm/bcm7425.dtsi | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/boot/dts/brcm/bcm7425.dtsi b/arch/mips/boot/dts/brcm/bcm7425.dtsi index 410e61ebaf9e..aa0b2d39c902 100644 --- a/arch/mips/boot/dts/brcm/bcm7425.dtsi +++ b/arch/mips/boot/dts/brcm/bcm7425.dtsi @@ -403,8 +403,8 @@ compatible = "brcm,brcmnand-v5.0", "brcm,brcmnand"; #address-cells = <1>; #size-cells = <0>; - reg-names = "nand"; - reg = <0x41b800 0x400>; + reg-names = "nand", "flash-edu"; + reg = <0x41b800 0x400>, <0x41bc00 0x24>; interrupt-parent = <&hif_l2_intc>; interrupts = <24>; status = "disabled";

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 | 293 ++++++++++++++++++++++- 1 file changed, 287 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c index 1a66b1cd51c0..2185ff1c3fee 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; + 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 +1783,81 @@ 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; + 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 +2064,11 @@ 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 +2204,12 @@ 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 +2712,8 @@ 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 +2728,14 @@ 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 +2781,49 @@ 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 (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); + } + } + + return 0; +}

int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc) { @@ -2578,6 +2849,7 @@ 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); @@ -2665,6 +2937,15 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc) }

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

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