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dt: bindings: brcmnand: Add support for flash-edu

PATCH Superseded Kamal Dasu 3 participants 6 messages Jan 22, 2020 – Jan 23, 2020

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v3 of 4 Superseded Latest is v4 →

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Kamal Dasu

author
#0 lore raw

PATCH v3 1/3 dt: bindings: brcmnand: Add support for flash-edu

Adding support for EBI DMA unit (EDU).

---
 .../devicetree/bindings/mtd/brcm,brcmnand.txt          | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt +5 -5
index 82156dc8f304..05651a654c66 100644
@@ -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
Signature · 1 line
2.17.1
author
#1 lore raw

PATCH v3 2/3 arch: mips: brcm: Add 7425 flash-edu support

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.

---
 arch/mips/boot/dts/brcm/bcm7425.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
arch/mips/boot/dts/brcm/bcm7425.dtsi +2 -2
index 410e61ebaf9e..aa0b2d39c902 100644
@@ -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";
Signature · 1 line
2.17.1
#2 lore raw

Re: [PATCH V3 2/3] arch: mips: brcm: Add 7425 flash-edu support

Quoted 5 lines · Kamal Dasu

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.

You can send your patches with a cover letter (git format-patch --cover-letter) and indicate what you changed between v2 and v3 in the cover letter so as to make it easier for reviewers/maintainers to figure out the differences and what to review specifically from the previous version.

Thanks!

Quoted 20 lines
---
 arch/mips/boot/dts/brcm/bcm7425.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
arch/mips/boot/dts/brcm/bcm7425.dtsi +2 -2
index 410e61ebaf9e..aa0b2d39c902 100644
@@ -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";
Signature · 1 line
Florian
author
#3 lore raw

PATCH v3 3/3 mtd: rawnand: brcmnand: Add support for flash-edu for dma transfers

In reply to Kamal Dasu

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.

---
 drivers/mtd/nand/raw/brcmnand/brcmnand.c | 296 ++++++++++++++++++++++-
 1 file changed, 290 insertions(+), 6 deletions(-)
drivers/mtd/nand/raw/brcmnand/brcmnand.c +290 -6
index 1a66b1cd51c0..61347607f1da 100644
@@ -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 */
Signature · 1 line
2.17.1
maintainer
#4 lore raw
In reply to Kamal Dasu
Quoted 7 lines · Kamal Dasu

Adding support for EBI DMA unit (EDU).

---
 .../devicetree/bindings/mtd/brcm,brcmnand.txt          | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Please add Acked-by/Reviewed-by tags when posting new versions. However, there's no need to repost patches *only* to add the tags. The upstream maintainer will do that for acks received on the version they apply.

If a tag was not added on purpose, please state why and what changed.

author
#5 lore raw

Rob,

Added tags to latest v4 patch set.

Thank You
Kamal

Quoted 16 lines · Rob Herring
Quoted 7 lines · Kamal Dasu

Adding support for EBI DMA unit (EDU).

---
.../devicetree/bindings/mtd/brcm,brcmnand.txt | 10 +++++-----

1 file changed, 5 insertions(+), 5 deletions(-)

Please add Acked-by/Reviewed-by tags when posting new versions. However, there's no need to repost patches *only* to add the tags. The upstream maintainer will do that for acks received on the version they apply.

If a tag was not added on purpose, please state why and what changed.