* [PATCH 3/3] mtd: rawnand: brcmnand: Add support for flash-edu for dma transfers
2019-11-20 18:20 [PATCH 1/3] dt: bindings: brcmnand: Add support for flash-edu Kamal Dasu
2019-11-20 18:20 ` [PATCH 2/3] arch: mips: brcm: Add 7425 flash-edu support Kamal Dasu
@ 2019-11-20 18:20 ` Kamal Dasu
2020-01-09 16:10 ` Miquel Raynal
2019-12-04 19:12 ` [PATCH 1/3] dt: bindings: brcmnand: Add support for flash-edu Rob Herring
2 siblings, 1 reply; 5+ messages in thread
From: Kamal Dasu @ 2019-11-20 18:20 UTC (permalink / raw)
To: linux-mtd
Cc: Vignesh Raghavendra, Kamal Dasu, Richard Weinberger, linux-kernel,
Marek Vasut, bcm-kernel-feedback-list, Miquel Raynal,
Brian Norris, David Woodhouse
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 | 269 ++++++++++++++++++++++-
1 file changed, 263 insertions(+), 6 deletions(-)
diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 15ef30b368a5..05663e3ef20f 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -102,6 +102,44 @@ 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_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,
@@ -155,6 +193,8 @@ enum {
BRCMNAND_HAS_WP = BIT(3),
};
+struct brcmnand_host;
+
struct brcmnand_controller {
struct device *dev;
struct nand_controller controller;
@@ -173,17 +213,32 @@ 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];
@@ -204,6 +259,7 @@ struct brcmnand_controller {
u32 nand_cs_nand_xor;
u32 corr_stat_threshold;
u32 flash_dma_mode;
+ u32 flash_edu_mode;
bool pio_poll_mode;
};
@@ -643,6 +699,22 @@ 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)
{
@@ -912,6 +984,16 @@ 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)
@@ -1285,6 +1367,40 @@ static int write_oob_to_regs(struct brcmnand_controller *ctrl, int i,
return tbytes;
}
+/* 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))
+ udelay(1);
+ edu_writel(ctrl, EDU_DONE, 0);
+ (void)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);
+ (void)edu_readl(ctrl, EDU_DRAM_ADDR);
+ edu_writel(ctrl, EDU_EXT_ADDR, ctrl->edu_ext_addr);
+ (void)edu_readl(ctrl, EDU_EXT_ADDR);
+
+ mb(); /* flush previous writes */
+ edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd);
+ (void)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;
@@ -1293,6 +1409,16 @@ 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;
}
@@ -1630,6 +1756,82 @@ 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 edu_cmd)
+{
+ struct brcmnand_controller *ctrl = host->ctrl;
+ unsigned long timeo = msecs_to_jiffies(200);
+ int ret = 0;
+ int dir = edu_cmd == EDU_CMD_READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+ unsigned int trans = len/FC_BYTES;
+ 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;
+ }
+
+ /* Start edu engine */
+ 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);
+ (void)brcmnand_read_reg(ctrl, EDU_DRAM_ADDR);
+ edu_writel(ctrl, EDU_EXT_ADDR, ctrl->edu_ext_addr);
+ (void)edu_readl(ctrl, EDU_EXT_ADDR);
+ edu_writel(ctrl, EDU_LENGTH, FC_BYTES);
+ (void)edu_readl(ctrl, EDU_LENGTH);
+
+ mb(); /* flush previous writes */
+ edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd);
+ (void)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;
+ }
+
+ edu_writel(ctrl, EDU_ERR_STATUS, 0);
+
+ ctrl->edu_pending = false;
+ edu_writel(ctrl, EDU_STOP, 0); /* force stop */
+
+ return ret;
+}
+
/**
* Construct a FLASH_DMA descriptor as part of a linked list. You must know the
* following ahead of time:
@@ -1833,9 +2035,11 @@ 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;
@@ -1971,10 +2175,12 @@ 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;
}
@@ -2561,6 +2767,7 @@ 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);
@@ -2650,6 +2857,56 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
dev_info(dev, "enabling FLASH_DMA\n");
}
+ /* use EDU DMA only no FLASH_DMA present */
+ if (has_flash_dma(ctrl))
+ res = 0;
+ else
+ 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);
+ (void)edu_readl(ctrl, EDU_CONFIG);
+
+ /* initialize edu */
+ edu_writel(ctrl, EDU_ERR_STATUS, 0);
+ edu_writel(ctrl, EDU_DONE, 0);
+ (void)edu_readl(ctrl, EDU_DONE);
+
+ ctrl->edu_irq = platform_get_irq(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(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 dma transfer function to call */
+ if (has_flash_dma(ctrl))
+ ctrl->dma_trans = brcmnand_dma_trans;
+ else if (has_edu(ctrl))
+ ctrl->dma_trans = brcmnand_edu_trans;
+ else
+ ctrl->dma_trans = NULL;
+
/* Disable automatic device ID config, direct addressing */
brcmnand_rmw_reg(ctrl, BRCMNAND_CS_SELECT,
CS_SELECT_AUTO_DEVICE_ID_CFG | 0xff, 0, 0);
--
2.17.1
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