[PATCH 5.10 062/129] memory: renesas-rpc-if: Fix HF/OSPI data transfer in Manual Mode

Greg Kroah-Hartman
2022-05-04T17:01:49Z

From: Geert Uytterhoeven <geert+renesas@glider.be>

[ Upstream commit 7e842d70fe599bc13594b650b2144c4b6e6d6bf1 ]

HyperFlash devices fail to probe:

rpc-if-hyperflash rpc-if-hyperflash: probing of hyperbus device failed

In HyperFlash or Octal-SPI Flash mode, the Transfer Data Enable bits
(SPIDE) in the Manual Mode Enable Setting Register (SMENR) are derived
from half of the transfer size, cfr. the rpcif_bits_set() helper
function. However, rpcif_reg_{read,write}() does not take the bus size
into account, and does not double all Manual Mode Data Register access
sizes when communicating with a HyperFlash or Octal-SPI Flash device.

Fix this, and avoid the back-and-forth conversion between transfer size
and Transfer Data Enable bits, by explicitly storing the transfer size
in struct rpcif, and using that value to determine access size in
rpcif_reg_{read,write}().

Enforce that the "high" Manual Mode Read/Write Data Registers
(SM[RW]DR1) are only used for 8-byte data accesses.
While at it, forbid writing to the Manual Mode Read Data Registers,
as they are read-only.

Fixes: fff53a551db50f5e ("memory: renesas-rpc-if: Correct QSPI data transfer in Manual mode")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/cde9bfacf704c81865f57b15d1b48a4793da4286.1649681476.git.geert+renesas@glider.be
Link: https://lore.kernel.org/r/20220420070526.9367-1-krzysztof.kozlowski@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/memory/renesas-rpc-if.c | 60 +++++++++++++++++++++++++--------
include/memory/renesas-rpc-if.h | 1 +
2 files changed, 47 insertions(+), 14 deletions(-)

diff --git a/drivers/memory/renesas-rpc-if.c b/drivers/memory/renesas-rpc-if.c
index 781af51e3f79..1dfb81dea961 100644
--- a/drivers/memory/renesas-rpc-if.c
+++ b/drivers/memory/renesas-rpc-if.c
@@ -163,25 +163,39 @@ static const struct regmap_access_table rpcif_volatile_table = {

/*
- * Custom accessor functions to ensure SMRDR0 and SMWDR0 are always accessed
- * with proper width. Requires SMENR_SPIDE to be correctly set before!
+ * Custom accessor functions to ensure SM[RW]DR[01] are always accessed with
+ * proper width. Requires rpcif.xfer_size to be correctly set before!
*/
static int rpcif_reg_read(void *context, unsigned int reg, unsigned int *val)
{
struct rpcif *rpc = context;

- if (reg == RPCIF_SMRDR0 || reg == RPCIF_SMWDR0) {
- u32 spide = readl(rpc->base + RPCIF_SMENR) & RPCIF_SMENR_SPIDE(0xF);
-
- if (spide == 0x8) {
+ switch (reg) {
+ case RPCIF_SMRDR0:
+ case RPCIF_SMWDR0:
+ switch (rpc->xfer_size) {
+ case 1:
*val = readb(rpc->base + reg);
return 0;
- } else if (spide == 0xC) {
+
+ case 2:
*val = readw(rpc->base + reg);
return 0;
- } else if (spide != 0xF) {
+
+ case 4:
+ case 8:
+ *val = readl(rpc->base + reg);
+ return 0;
+
+ default:
return -EILSEQ;
}
+
+ case RPCIF_SMRDR1:
+ case RPCIF_SMWDR1:
+ if (rpc->xfer_size != 8)
+ return -EILSEQ;
+ break;
}

*val = readl(rpc->base + reg);
@@ -193,18 +207,34 @@ static int rpcif_reg_write(void *context, unsigned int reg, unsigned int val)
{
struct rpcif *rpc = context;

- if (reg == RPCIF_SMRDR0 || reg == RPCIF_SMWDR0) {
- u32 spide = readl(rpc->base + RPCIF_SMENR) & RPCIF_SMENR_SPIDE(0xF);
-
- if (spide == 0x8) {
+ switch (reg) {
+ case RPCIF_SMWDR0:
+ switch (rpc->xfer_size) {
+ case 1:
writeb(val, rpc->base + reg);
return 0;
- } else if (spide == 0xC) {
+
+ case 2:
writew(val, rpc->base + reg);
return 0;
- } else if (spide != 0xF) {
+
+ case 4:
+ case 8:
+ writel(val, rpc->base + reg);
+ return 0;
+
+ default:
return -EILSEQ;
}
+
+ case RPCIF_SMWDR1:
+ if (rpc->xfer_size != 8)
+ return -EILSEQ;
+ break;
+
+ case RPCIF_SMRDR0:
+ case RPCIF_SMRDR1:
+ return -EPERM;
}

writel(val, rpc->base + reg);
@@ -455,6 +485,7 @@ int rpcif_manual_xfer(struct rpcif *rpc)

smenr |= RPCIF_SMENR_SPIDE(rpcif_bits_set(rpc, nbytes));
regmap_write(rpc->regmap, RPCIF_SMENR, smenr);
+ rpc->xfer_size = nbytes;

memcpy(data, rpc->buffer + pos, nbytes);
if (nbytes == 8) {
@@ -519,6 +550,7 @@ int rpcif_manual_xfer(struct rpcif *rpc)
regmap_write(rpc->regmap, RPCIF_SMENR, smenr);
regmap_write(rpc->regmap, RPCIF_SMCR,
rpc->smcr | RPCIF_SMCR_SPIE);
+ rpc->xfer_size = nbytes;
ret = wait_msg_xfer_end(rpc);
if (ret)
goto err_out;
diff --git a/include/memory/renesas-rpc-if.h b/include/memory/renesas-rpc-if.h
index aceb2c360d3f..0e3dac030219 100644
--- a/include/memory/renesas-rpc-if.h
+++ b/include/memory/renesas-rpc-if.h
@@ -65,6 +65,7 @@ struct rpcif {
size_t size;
enum rpcif_data_dir dir;
u8 bus_size;
+ u8 xfer_size;
void *buffer;
u32 xferlen;
u32 smcr;
--
2.35.1