mtd: bcm47xxnflash: implement reading

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

2 files changed, 107 insertions, 0 deletions

diff --git a/drivers/mtd/nand/bcm47xxnflash/bcm47xxnflash.h b/drivers/mtd/nand/bcm47xxnflash/bcm47xxnflash.h
index cc71400de116..264aec448fc4 100644
--- a/drivers/mtd/nand/bcm47xxnflash/bcm47xxnflash.h
+++ b/drivers/mtd/nand/bcm47xxnflash/bcm47xxnflash.h
@@ -11,6 +11,7 @@ struct bcm47xxnflash {
         struct mtd_info mtd;
 
         unsigned curr_command;
+        int curr_page_addr;
         int curr_column;
 
         u8 id_data[8];
diff --git a/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
index 7de190e9a788..e42e18208abc 100644
--- a/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
+++ b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
@@ -20,6 +20,8 @@
  * shown 164 retries as maxiumum. */
 #define NFLASH_READY_RETRIES            1000
 
+#define NFLASH_SECTOR_SIZE              512
+
 /**************************************************
  * Various helpers
  **************************************************/
@@ -47,6 +49,80 @@ static int bcm47xxnflash_ops_bcm4706_ctl_cmd(struct bcma_drv_cc *cc, u32 code)
         return 0;
 }
 
+static int bcm47xxnflash_ops_bcm4706_poll(struct bcma_drv_cc *cc)
+{
+        int i;
+
+        for (i = 0; i < NFLASH_READY_RETRIES; i++) {
+                if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) & 0x04000000) {
+                        if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) &
+                            BCMA_CC_NFLASH_CTL_ERR) {
+                                pr_err("Error on polling\n");
+                                return -EBUSY;
+                        } else {
+                                return 0;
+                        }
+                }
+        }
+
+        pr_err("Polling timeout!\n");
+        return -EBUSY;
+}
+
+/**************************************************
+ * R/W
+ **************************************************/
+
+static void bcm47xxnflash_ops_bcm4706_read(struct mtd_info *mtd, uint8_t *buf,
+                                           int len)
+{
+        struct nand_chip *nand_chip = (struct nand_chip *)mtd->priv;
+        struct bcm47xxnflash *b47n = (struct bcm47xxnflash *)nand_chip->priv;
+
+        u32 ctlcode;
+        u32 *dest = (u32 *)buf;
+        int i;
+        int toread;
+
+        BUG_ON(b47n->curr_page_addr & ~nand_chip->pagemask);
+        /* Don't validate column using nand_chip->page_shift, it may be bigger
+         * when accessing OOB */
+
+        while (len) {
+                /* We can read maximum of 0x200 bytes at once */
+                toread = min(len, 0x200);
+
+                /* Set page and column */
+                bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_COL_ADDR,
+                                b47n->curr_column);
+                bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_ROW_ADDR,
+                                b47n->curr_page_addr);
+
+                /* Prepare to read */
+                ctlcode = 0x40000000 | 0x00080000 | 0x00040000 | 0x00020000 |
+                          0x00010000;
+                ctlcode |= NAND_CMD_READSTART << 8;
+                if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc, ctlcode))
+                        return;
+                if (bcm47xxnflash_ops_bcm4706_poll(b47n->cc))
+                        return;
+
+                /* Eventually read some data :) */
+                for (i = 0; i < toread; i += 4, dest++) {
+                        ctlcode = 0x40000000 | 0x30000000 | 0x00100000;
+                        if (i == toread - 4) /* Last read goes without that */
+                                ctlcode &= ~0x40000000;
+                        if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc,
+                                                              ctlcode))
+                                return;
+                        *dest = bcma_cc_read32(b47n->cc, BCMA_CC_NFLASH_DATA);
+                }
+
+                b47n->curr_column += toread;
+                len -= toread;
+        }
+}
+
 /**************************************************
  * NAND chip ops
  **************************************************/
@@ -76,6 +152,8 @@ static void bcm47xxnflash_ops_bcm4706_cmdfunc(struct mtd_info *mtd,
 
         if (column != -1)
                 b47n->curr_column = column;
+        if (page_addr != -1)
+                b47n->curr_page_addr = page_addr;
 
         switch (command) {
         case NAND_CMD_RESET:
@@ -109,6 +187,12 @@ static void bcm47xxnflash_ops_bcm4706_cmdfunc(struct mtd_info *mtd,
                 }
 
                 break;
+        case NAND_CMD_READ0:
+                break;
+        case NAND_CMD_READOOB:
+                if (page_addr != -1)
+                        b47n->curr_column += mtd->writesize;
+                break;
         default:
                 pr_err("Command 0x%X unsupported\n", command);
                 break;
@@ -120,6 +204,7 @@ static u8 bcm47xxnflash_ops_bcm4706_read_byte(struct mtd_info *mtd)
 {
         struct nand_chip *nand_chip = (struct nand_chip *)mtd->priv;
         struct bcm47xxnflash *b47n = (struct bcm47xxnflash *)nand_chip->priv;
+        u32 tmp = 0;
 
         switch (b47n->curr_command) {
         case NAND_CMD_READID:
@@ -129,12 +214,31 @@ static u8 bcm47xxnflash_ops_bcm4706_read_byte(struct mtd_info *mtd)
                         return 0;
                 }
                 return b47n->id_data[b47n->curr_column++];
+        case NAND_CMD_READOOB:
+                bcm47xxnflash_ops_bcm4706_read(mtd, (u8 *)&tmp, 4);
+                return tmp & 0xFF;
         }
 
         pr_err("Invalid command for byte read: 0x%X\n", b47n->curr_command);
         return 0;
 }
 
+static void bcm47xxnflash_ops_bcm4706_read_buf(struct mtd_info *mtd,
+                                               uint8_t *buf, int len)
+{
+        struct nand_chip *nand_chip = (struct nand_chip *)mtd->priv;
+        struct bcm47xxnflash *b47n = (struct bcm47xxnflash *)nand_chip->priv;
+
+        switch (b47n->curr_command) {
+        case NAND_CMD_READ0:
+        case NAND_CMD_READOOB:
+                bcm47xxnflash_ops_bcm4706_read(mtd, buf, len);
+                return;
+        }
+
+        pr_err("Invalid command for buf read: 0x%X\n", b47n->curr_command);
+}
+
 /**************************************************
  * Init
  **************************************************/
@@ -153,6 +257,8 @@ int bcm47xxnflash_ops_bcm4706_init(struct bcm47xxnflash *b47n)
         b47n->nand_chip.select_chip = bcm47xxnflash_ops_bcm4706_select_chip;
         b47n->nand_chip.cmdfunc = bcm47xxnflash_ops_bcm4706_cmdfunc;
         b47n->nand_chip.read_byte = bcm47xxnflash_ops_bcm4706_read_byte;
+        b47n->nand_chip.read_buf = bcm47xxnflash_ops_bcm4706_read_buf;
+        b47n->nand_chip.bbt_options = NAND_BBT_USE_FLASH;
         b47n->nand_chip.ecc.mode = NAND_ECC_NONE; /* TODO: implement ECC */
 
         /* Enable NAND flash access */