From: Dmitry Baryshkov dmitry.baryshkov@linaro.org
[ Upstream commit 3566a737db87a9bf360c2fd36433c5149f805f2e ]
All platforms since Snapdragon 8 Gen1 (SM8450) require using 4-byte reads to access QFPROM data. While older platforms were more than happy with 1-byte reads, change the qfprom driver to use 4-byte reads for all the platforms. Specify stride and word size of 4 bytes. To retain compatibility with the existing DT and to simplify porting data from vendor kernels, use fixup_dt_cell_info in order to bump alignment requirements.
Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Link: https://lore.kernel.org/r/20250411112251.68002-12-srinivas.kandagatla@linaro... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvmem/qfprom.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-)
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c index 116a39e804c70..a872c640b8c5a 100644 --- a/drivers/nvmem/qfprom.c +++ b/drivers/nvmem/qfprom.c @@ -321,19 +321,32 @@ static int qfprom_reg_read(void *context, unsigned int reg, void *_val, size_t bytes) { struct qfprom_priv *priv = context; - u8 *val = _val; - int i = 0, words = bytes; + u32 *val = _val; void __iomem *base = priv->qfpcorrected; + int words = DIV_ROUND_UP(bytes, sizeof(u32)); + int i;
if (read_raw_data && priv->qfpraw) base = priv->qfpraw;
- while (words--) - *val++ = readb(base + reg + i++); + for (i = 0; i < words; i++) + *val++ = readl(base + reg + i * sizeof(u32));
return 0; }
+/* Align reads to word boundary */ +static void qfprom_fixup_dt_cell_info(struct nvmem_device *nvmem, + struct nvmem_cell_info *cell) +{ + unsigned int byte_offset = cell->offset % sizeof(u32); + + cell->bit_offset += byte_offset * BITS_PER_BYTE; + cell->offset -= byte_offset; + if (byte_offset && !cell->nbits) + cell->nbits = cell->bytes * BITS_PER_BYTE; +} + static void qfprom_runtime_disable(void *data) { pm_runtime_disable(data); @@ -358,10 +371,11 @@ static int qfprom_probe(struct platform_device *pdev) struct nvmem_config econfig = { .name = "qfprom", .add_legacy_fixed_of_cells = true, - .stride = 1, - .word_size = 1, + .stride = 4, + .word_size = 4, .id = NVMEM_DEVID_AUTO, .reg_read = qfprom_reg_read, + .fixup_dt_cell_info = qfprom_fixup_dt_cell_info, }; struct device *dev = &pdev->dev; struct resource *res;