mtd: rawnand: brcmnand: read/write oob during EDU transfer

Added support to read/write oob during EDU transfers.
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210311170909.9031-1-kdasu.kdev@gmail.com

drivers/mtd/nand/raw/brcmnand/brcmnand.c

@@ -242,6 +242,9 @@ struct brcmnand_controller {
 	u32                     edu_ext_addr;
 	u32                     edu_cmd;
 	u32                     edu_config;
+	int			sas; /* spare area size, per flash cache */
+	int			sector_size_1k;
+	u8			*oob;
 
 	/* flash_dma reg */
 	const u16		*flash_dma_offsets;
@@ -249,7 +252,7 @@ struct brcmnand_controller {
 	dma_addr_t		dma_pa;
 
 	int (*dma_trans)(struct brcmnand_host *host, u64 addr, u32 *buf,
-			 u32 len, u8 dma_cmd);
+			 u8 *oob, u32 len, u8 dma_cmd);
 
 	/* in-memory cache of the FLASH_CACHE, used only for some commands */
 	u8			flash_cache[FC_BYTES];
@@ -1479,6 +1482,23 @@ static irqreturn_t brcmnand_edu_irq(int irq, void *data)
 		edu_writel(ctrl, EDU_EXT_ADDR, ctrl->edu_ext_addr);
 		edu_readl(ctrl, EDU_EXT_ADDR);
 
+		if (ctrl->oob) {
+			if (ctrl->edu_cmd == EDU_CMD_READ) {
+				ctrl->oob += read_oob_from_regs(ctrl,
+							ctrl->edu_count + 1,
+							ctrl->oob, ctrl->sas,
+							ctrl->sector_size_1k);
+			} else {
+				brcmnand_write_reg(ctrl, BRCMNAND_CMD_ADDRESS,
+						   ctrl->edu_ext_addr);
+				brcmnand_read_reg(ctrl, BRCMNAND_CMD_ADDRESS);
+				ctrl->oob += write_oob_to_regs(ctrl,
+							       ctrl->edu_count,
+							       ctrl->oob, ctrl->sas,
+							       ctrl->sector_size_1k);
+			}
+		}
+
 		mb(); /* flush previous writes */
 		edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd);
 		edu_readl(ctrl, EDU_CMD);
@@ -1850,9 +1870,10 @@ 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)
+			      u8 *oob, u32 len, u8 cmd)
 {
 	struct brcmnand_controller *ctrl = host->ctrl;
+	struct brcmnand_cfg *cfg = &host->hwcfg;
 	unsigned long timeo = msecs_to_jiffies(200);
 	int ret = 0;
 	int dir = (cmd == CMD_PAGE_READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
@@ -1860,6 +1881,9 @@ static int brcmnand_edu_trans(struct brcmnand_host *host, u64 addr, u32 *buf,
 	unsigned int trans = len >> FC_SHIFT;
 	dma_addr_t pa;
 
+	dev_dbg(ctrl->dev, "EDU %s %p:%p\n", ((edu_cmd == EDU_CMD_READ) ?
+					      "read" : "write"), buf, oob);
+
 	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");
@@ -1871,6 +1895,8 @@ static int brcmnand_edu_trans(struct brcmnand_host *host, u64 addr, u32 *buf,
 	ctrl->edu_ext_addr = addr;
 	ctrl->edu_cmd = edu_cmd;
 	ctrl->edu_count = trans;
+	ctrl->sas = cfg->spare_area_size;
+	ctrl->oob = oob;
 
 	edu_writel(ctrl, EDU_DRAM_ADDR, (u32)ctrl->edu_dram_addr);
 	edu_readl(ctrl,  EDU_DRAM_ADDR);
@@ -1879,6 +1905,16 @@ static int brcmnand_edu_trans(struct brcmnand_host *host, u64 addr, u32 *buf,
 	edu_writel(ctrl, EDU_LENGTH, FC_BYTES);
 	edu_readl(ctrl, EDU_LENGTH);
 
+	if (ctrl->oob && (ctrl->edu_cmd == EDU_CMD_WRITE)) {
+		brcmnand_write_reg(ctrl, BRCMNAND_CMD_ADDRESS,
+				   ctrl->edu_ext_addr);
+		brcmnand_read_reg(ctrl, BRCMNAND_CMD_ADDRESS);
+		ctrl->oob += write_oob_to_regs(ctrl,
+					       1,
+					       ctrl->oob, ctrl->sas,
+					       ctrl->sector_size_1k);
+	}
+
 	/* Start edu engine */
 	mb(); /* flush previous writes */
 	edu_writel(ctrl, EDU_CMD, ctrl->edu_cmd);
@@ -1893,6 +1929,14 @@ static int brcmnand_edu_trans(struct brcmnand_host *host, u64 addr, u32 *buf,
 
 	dma_unmap_single(ctrl->dev, pa, len, dir);
 
+	/* read last subpage oob */
+	if (ctrl->oob && (ctrl->edu_cmd == EDU_CMD_READ)) {
+		ctrl->oob += read_oob_from_regs(ctrl,
+						1,
+						ctrl->oob, ctrl->sas,
+						ctrl->sector_size_1k);
+	}
+
 	/* for program page check NAND status */
 	if (((brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS) &
 	      INTFC_FLASH_STATUS) & NAND_STATUS_FAIL) &&
@@ -2002,7 +2046,7 @@ static void brcmnand_dma_run(struct brcmnand_host *host, dma_addr_t desc)
 }
 
 static int brcmnand_dma_trans(struct brcmnand_host *host, u64 addr, u32 *buf,
-			      u32 len, u8 dma_cmd)
+			      u8 *oob, u32 len, u8 dma_cmd)
 {
 	struct brcmnand_controller *ctrl = host->ctrl;
 	dma_addr_t buf_pa;
@@ -2147,8 +2191,9 @@ static int brcmnand_read(struct mtd_info *mtd, struct nand_chip *chip,
 try_dmaread:
 	brcmnand_clear_ecc_addr(ctrl);
 
-	if (ctrl->dma_trans && !oob && flash_dma_buf_ok(buf)) {
-		err = ctrl->dma_trans(host, addr, buf,
+	if (ctrl->dma_trans && (has_edu(ctrl) || !oob) &&
+	    flash_dma_buf_ok(buf)) {
+		err = ctrl->dma_trans(host, addr, buf, oob,
 				      trans * FC_BYTES,
 				      CMD_PAGE_READ);
 
@@ -2296,8 +2341,8 @@ 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 (use_dma(ctrl) && !oob && flash_dma_buf_ok(buf)) {
-		if (ctrl->dma_trans(host, addr, (u32 *)buf, mtd->writesize,
+	if (use_dma(ctrl) && (has_edu(ctrl) || !oob) && flash_dma_buf_ok(buf)) {
+		if (ctrl->dma_trans(host, addr, (u32 *)buf, oob, mtd->writesize,
 				    CMD_PROGRAM_PAGE))
 
 			ret = -EIO;