mtd: rawnand: loongson: Add 6-byte NAND ID reading support

Loongson-1C and Loongson-2K SoCs support NAND flash chips with 6-byte ID.
However, the current implementation only handles 5-byte ID which can lead
to incorrect chip detection.

Extend loongson_nand_read_id_type_exec() to support 6-byte NAND ID.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/raw/loongson-nand-controller.c b/drivers/mtd/nand/raw/loongson-nand-controller.c
index b5a7be0fcaccbad12f9e8de8a2844c68edac0057..97cd566420a8935f60beabcf64d3369643507979 100644 (file)
--- a/drivers/mtd/nand/raw/loongson-nand-controller.c
+++ b/drivers/mtd/nand/raw/loongson-nand-controller.c
@@ -50,6 +50,9 @@
 #define LOONGSON_NAND_COL_ADDR_CYC     2U
 #define LOONGSON_NAND_MAX_ADDR_CYC     5U
 
+#define LOONGSON_NAND_READ_ID_SLEEP_US         1000
+#define LOONGSON_NAND_READ_ID_TIMEOUT_US       5000
+
 #define BITS_PER_WORD                  (4 * BITS_PER_BYTE)
 
 struct loongson_nand_host;
@@ -73,6 +76,8 @@ struct loongson_nand_op {
 };
 
 struct loongson_nand_data {
+       unsigned int max_id_cycle;
+       unsigned int id_cycle_field;
        unsigned int status_field;
        unsigned int op_scope_field;
        unsigned int hold_cycle;
@@ -458,10 +463,10 @@ static int loongson_nand_read_id_type_exec(struct nand_chip *chip, const struct
        struct loongson_nand_op op = {};
        int i, ret;
        union {
-               char ids[5];
+               char ids[6];
                struct {
                        int idl;
-                       char idh;
+                       u16 idh;
                };
        } nand_id;
 
@@ -469,11 +474,16 @@ static int loongson_nand_read_id_type_exec(struct nand_chip *chip, const struct
        if (ret)
                return ret;
 
-       nand_id.idl = readl(host->reg_base + LOONGSON_NAND_IDL);
-       nand_id.idh = readb(host->reg_base + LOONGSON_NAND_IDH_STATUS);
+       ret = regmap_read_poll_timeout(host->regmap, LOONGSON_NAND_IDL, nand_id.idl, nand_id.idl,
+                                      LOONGSON_NAND_READ_ID_SLEEP_US,
+                                      LOONGSON_NAND_READ_ID_TIMEOUT_US);
+       if (ret)
+               return ret;
 
-       for (i = 0; i < min(sizeof(nand_id.ids), op.orig_len); i++)
-               op.buf[i] = nand_id.ids[sizeof(nand_id.ids) - 1 - i];
+       nand_id.idh = readw(host->reg_base + LOONGSON_NAND_IDH_STATUS);
+
+       for (i = 0; i < min(host->data->max_id_cycle, op.orig_len); i++)
+               op.buf[i] = nand_id.ids[host->data->max_id_cycle - 1 - i];
 
        return ret;
 }
@@ -676,6 +686,10 @@ static int loongson_nand_controller_init(struct loongson_nand_host *host)
        if (IS_ERR(host->regmap))
                return dev_err_probe(dev, PTR_ERR(host->regmap), "failed to init regmap\n");
 
+       if (host->data->id_cycle_field)
+               regmap_update_bits(host->regmap, LOONGSON_NAND_PARAM, host->data->id_cycle_field,
+                                  host->data->max_id_cycle << __ffs(host->data->id_cycle_field));
+
        chan = dma_request_chan(dev, "rxtx");
        if (IS_ERR(chan))
                return dev_err_probe(dev, PTR_ERR(chan), "failed to request DMA channel\n");
@@ -800,6 +814,7 @@ static void loongson_nand_remove(struct platform_device *pdev)
 }
 
 static const struct loongson_nand_data ls1b_nand_data = {
+       .max_id_cycle = 5,
        .status_field = GENMASK(15, 8),
        .hold_cycle = 0x2,
        .wait_cycle = 0xc,
@@ -807,6 +822,8 @@ static const struct loongson_nand_data ls1b_nand_data = {
 };
 
 static const struct loongson_nand_data ls1c_nand_data = {
+       .max_id_cycle = 6,
+       .id_cycle_field = GENMASK(14, 12),
        .status_field = GENMASK(23, 16),
        .op_scope_field = GENMASK(29, 16),
        .hold_cycle = 0x2,