[PATCH 10/12] mtd: rawnand: brcmnand: Add BCMBCA read data bus interface

William Zhang
2023-06-06T23:15:19Z

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The BCMBCA broadband SoC integrates the NAND controller differently than
STB, iProc and other SoCs. It has different endianness for NAND cache
data and ONFI parameter data.

Add a SoC read data bus shim for BCMBCA to meet the specific SoC need
and performance improvement using the optimized memcpy function on NAND
cache memory.

Signed-off-by: William Zhang <william.zhang@broadcom.com>
---

drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c | 36 +++++++++++++++++
drivers/mtd/nand/raw/brcmnand/brcmnand.c | 44 ++++++++++++++-------
drivers/mtd/nand/raw/brcmnand/brcmnand.h | 2 +
3 files changed, 68 insertions(+), 14 deletions(-)

diff --git a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
index 7e48b6a0bfa2..899103a62c98 100644
--- a/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
+++ b/drivers/mtd/nand/raw/brcmnand/bcmbca_nand.c
@@ -26,6 +26,18 @@ enum {
BCMBCA_CTLRDY = BIT(4),
};

+#if defined(CONFIG_ARM64)
+#define ALIGN_REQ 8
+#else
+#define ALIGN_REQ 4
+#endif
+
+static inline bool bcmbca_nand_is_buf_aligned(void *flash_cache, void *buffer)
+{
+ return IS_ALIGNED((uintptr_t)buffer, ALIGN_REQ) &&
+ IS_ALIGNED((uintptr_t)flash_cache, ALIGN_REQ);
+}
+
static bool bcmbca_nand_intc_ack(struct brcmnand_soc *soc)
{
struct bcmbca_nand_soc *priv =
@@ -56,6 +68,29 @@ static void bcmbca_nand_intc_set(struct brcmnand_soc *soc, bool en)
brcmnand_writel(val, mmio);
}

+static void bcmbca_read_data_bus(struct brcmnand_soc *soc,
+ void __iomem *flash_cache, u32 *buffer,
+ int fc_words, bool is_param)
+{
+ int i;
+
+ if (!is_param) {
+ /*
+ * memcpy can do unaligned aligned access depending on source
+ * and dest address, which is incompatible with nand cache. Fallback
+ * to the memcpy for io version
+ */
+ if (bcmbca_nand_is_buf_aligned(flash_cache, buffer))
+ memcpy((void *)buffer, (void *)flash_cache, fc_words * 4);
+ else
+ memcpy_fromio((void *)buffer, (void *)flash_cache, fc_words * 4);
+ } else {
+ /* Flash cache has same endian as the host for parameter pages */
+ for (i = 0; i < fc_words; i++, buffer++)
+ *buffer = __raw_readl(flash_cache + i * 4);
+ }
+}
+
static int bcmbca_nand_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -75,6 +110,7 @@ static int bcmbca_nand_probe(struct platform_device *pdev)

soc->ctlrdy_ack = bcmbca_nand_intc_ack;
soc->ctlrdy_set_enabled = bcmbca_nand_intc_set;
+ soc->read_data_bus = bcmbca_read_data_bus;

return brcmnand_probe(pdev, soc);
}
diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index d920e88c7f5b..656be4d73016 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -814,6 +814,30 @@ static inline u32 edu_readl(struct brcmnand_controller *ctrl,
return brcmnand_readl(ctrl->edu_base + offs);
}

+static inline void brcmnand_read_data_bus(struct brcmnand_controller *ctrl,
+ void __iomem *flash_cache, u32 *buffer,
+ int fc_words, bool is_param)
+{
+ struct brcmnand_soc *soc = ctrl->soc;
+ int i;
+
+ if (soc->read_data_bus) {
+ soc->read_data_bus(soc, flash_cache, buffer, fc_words, is_param);
+ } else {
+ if (!is_param) {
+ for (i = 0; i < fc_words; i++, buffer++)
+ *buffer = brcmnand_read_fc(ctrl, i);
+ } else {
+ for (i = 0; i < fc_words; i++)
+ /*
+ * Flash cache is big endian for parameter pages, at
+ * least on STB SoCs
+ */
+ buffer[i] = be32_to_cpu(brcmnand_read_fc(ctrl, i));
+ }
+ }
+}
+
static void brcmnand_clear_ecc_addr(struct brcmnand_controller *ctrl)
{

@@ -1811,20 +1835,11 @@ static void brcmnand_cmdfunc(struct nand_chip *chip, unsigned command,
native_cmd == CMD_PARAMETER_CHANGE_COL) {
/* Copy flash cache word-wise */
u32 *flash_cache = (u32 *)ctrl->flash_cache;
- int i;

brcmnand_soc_data_bus_prepare(ctrl->soc, true);

- /*
- * Must cache the FLASH_CACHE now, since changes in
- * SECTOR_SIZE_1K may invalidate it
- */
- for (i = 0; i < FC_WORDS; i++)
- /*
- * Flash cache is big endian for parameter pages, at
- * least on STB SoCs
- */
- flash_cache[i] = be32_to_cpu(brcmnand_read_fc(ctrl, i));
+ brcmnand_read_data_bus(ctrl, ctrl->nand_fc, flash_cache,
+ FC_WORDS, true);

brcmnand_soc_data_bus_unprepare(ctrl->soc, true);

@@ -2137,7 +2152,7 @@ static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
{
struct brcmnand_host *host = nand_get_controller_data(chip);
struct brcmnand_controller *ctrl = host->ctrl;
- int i, j, ret = 0;
+ int i, ret = 0;

brcmnand_clear_ecc_addr(ctrl);

@@ -2150,8 +2165,9 @@ static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
if (likely(buf)) {
brcmnand_soc_data_bus_prepare(ctrl->soc, false);

- for (j = 0; j < FC_WORDS; j++, buf++)
- *buf = brcmnand_read_fc(ctrl, j);
+ brcmnand_read_data_bus(ctrl, ctrl->nand_fc, buf,
+ FC_WORDS, false);
+ buf += FC_WORDS;

brcmnand_soc_data_bus_unprepare(ctrl->soc, false);
}
diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.h b/drivers/mtd/nand/raw/brcmnand/brcmnand.h
index f1f93d85f50d..88819bc395f8 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.h
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.h
@@ -24,6 +24,8 @@ struct brcmnand_soc {
void (*ctlrdy_set_enabled)(struct brcmnand_soc *soc, bool en);
void (*prepare_data_bus)(struct brcmnand_soc *soc, bool prepare,
bool is_param);
+ void (*read_data_bus)(struct brcmnand_soc *soc, void __iomem *flash_cache,
+ u32 *buffer, int fc_words, bool is_param);
const struct brcmnand_io_ops *ops;
};

--
2.37.3