mtd: rawnand: sunxi: Precompute the ECC_CTL register value

The value computed by this function never changes for a given chip.
Compute the whole register value once up front, instead of every time
the ECC engine is enabled.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230204143520.9682-4-samuel@sholland.org

diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
index a0d0cb1..13e3e01 100644 (file)
--- a/drivers/mtd/nand/raw/sunxi_nand.c
+++ b/drivers/mtd/nand/raw/sunxi_nand.c
@@ -172,10 +172,10 @@ struct sunxi_nand_chip_sel {
 /**
  * struct sunxi_nand_hw_ecc - stores information related to HW ECC support
  *
- * @mode: the sunxi ECC mode field deduced from ECC requirements
+ * @ecc_ctl: ECC_CTL register value for this NAND chip
  */
 struct sunxi_nand_hw_ecc {
-       int mode;
+       u32 ecc_ctl;
 };
 
 /**
@@ -689,26 +689,15 @@ static void sunxi_nfc_hw_ecc_enable(struct nand_chip *nand)
 {
        struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
        struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
-       u32 ecc_ctl;
-
-       ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL);
-       ecc_ctl &= ~(NFC_ECC_MODE_MSK | NFC_ECC_PIPELINE |
-                    NFC_ECC_BLOCK_SIZE_MSK);
-       ecc_ctl |= NFC_ECC_EN | NFC_ECC_MODE(sunxi_nand->ecc.mode) |
-                  NFC_ECC_EXCEPTION | NFC_ECC_PIPELINE;
-
-       if (nand->ecc.size == 512)
-               ecc_ctl |= NFC_ECC_BLOCK_512;
 
-       writel(ecc_ctl, nfc->regs + NFC_REG_ECC_CTL);
+       writel(sunxi_nand->ecc.ecc_ctl, nfc->regs + NFC_REG_ECC_CTL);
 }
 
 static void sunxi_nfc_hw_ecc_disable(struct nand_chip *nand)
 {
        struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
 
-       writel(readl(nfc->regs + NFC_REG_ECC_CTL) & ~NFC_ECC_EN,
-              nfc->regs + NFC_REG_ECC_CTL);
+       writel(0, nfc->regs + NFC_REG_ECC_CTL);
 }
 
 static inline void sunxi_nfc_user_data_to_buf(u32 user_data, u8 *buf)
@@ -1693,8 +1682,6 @@ static int sunxi_nand_hw_ecc_ctrl_init(struct nand_chip *nand,
                return -ENOTSUPP;
        }
 
-       sunxi_nand->ecc.mode = i;
-
        /* HW ECC always request ECC bytes for 1024 bytes blocks */
        ecc->bytes = DIV_ROUND_UP(ecc->strength * fls(8 * 1024), 8);
 
@@ -1726,6 +1713,12 @@ static int sunxi_nand_hw_ecc_ctrl_init(struct nand_chip *nand,
        ecc->read_oob_raw = nand_read_oob_std;
        ecc->write_oob_raw = nand_write_oob_std;
 
+       sunxi_nand->ecc.ecc_ctl = NFC_ECC_MODE(i) | NFC_ECC_EXCEPTION |
+                                 NFC_ECC_PIPELINE | NFC_ECC_EN;
+
+       if (ecc->size == 512)
+               sunxi_nand->ecc.ecc_ctl |= NFC_ECC_BLOCK_512;
+
        return 0;
 }