[<prev] [next>] [day] [month] [year] [list]
Message-ID: <20250316191900.1858944-1-jonas@kwiboo.se>
Date: Sun, 16 Mar 2025 19:18:58 +0000
From: Jonas Karlman <jonas@...boo.se>
To: Heiko Stuebner <heiko@...ech.de>,
Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
Cc: linux-rockchip@...ts.infradead.org,
Jonas Karlman <jonas@...boo.se>,
linux-arm-kernel@...ts.infradead.org,
linux-kernel@...r.kernel.org
Subject: [PATCH] nvmem: rockchip-otp: Handle internal word_size in main reg_read op
Rockchip SoCs RK3576 and RK3588 read data from the OTP using 32-bit
words instead of normal 8-bit bytes. Similar RK3506, RK3528, RK3562 and
RK3568 will read data from OTP using 16-bit words.
The nvmem core stride and word_size cannot fully be used as cells is not
always aligned. Continue to report a stride=1 and word_size=1 in
nvmem_config and instead handle use of SoC specific word_size internally
in the driver.
Move current SoC specific word_size handling from the RK3588 read_reg
operation to the main read_reg operation to help simplify the SoC
specific read_reg operation and allow code reuse in a future RK3568
reg_read operation.
Signed-off-by: Jonas Karlman <jonas@...boo.se>
---
This closely matches how I refactored the Rockchip eFUSE and OTP driver
in mainline U-Boot to handle word/block reads back in 2023, see [1].
[1] http://lore.kernel.org/r/20230222224436.1570224-3-jonas@kwiboo.se/
---
drivers/nvmem/rockchip-otp.c | 72 ++++++++++++++++++++----------------
1 file changed, 40 insertions(+), 32 deletions(-)
diff --git a/drivers/nvmem/rockchip-otp.c b/drivers/nvmem/rockchip-otp.c
index d88f12c53242..45bbb6147fb7 100644
--- a/drivers/nvmem/rockchip-otp.c
+++ b/drivers/nvmem/rockchip-otp.c
@@ -59,7 +59,6 @@
#define RK3588_OTPC_AUTO_EN 0x08
#define RK3588_OTPC_INT_ST 0x84
#define RK3588_OTPC_DOUT0 0x20
-#define RK3588_NBYTES 4
#define RK3588_BURST_NUM 1
#define RK3588_BURST_SHIFT 8
#define RK3588_ADDR_SHIFT 16
@@ -69,6 +68,7 @@
struct rockchip_data {
int size;
int read_offset;
+ int word_size;
const char * const *clks;
int num_clks;
nvmem_reg_read_t reg_read;
@@ -185,48 +185,28 @@ static int px30_otp_read(void *context, unsigned int offset,
}
static int rk3588_otp_read(void *context, unsigned int offset,
- void *val, size_t bytes)
+ void *val, size_t count)
{
struct rockchip_otp *otp = context;
- unsigned int addr_start, addr_end, addr_len;
- int ret, i = 0;
- u32 data;
- u8 *buf;
-
- addr_start = round_down(offset, RK3588_NBYTES) / RK3588_NBYTES;
- addr_end = round_up(offset + bytes, RK3588_NBYTES) / RK3588_NBYTES;
- addr_len = addr_end - addr_start;
- addr_start += otp->data->read_offset / RK3588_NBYTES;
-
- buf = kzalloc(array_size(addr_len, RK3588_NBYTES), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ u32 *buf = val;
+ int ret;
- while (addr_len--) {
- writel((addr_start << RK3588_ADDR_SHIFT) |
+ while (count--) {
+ writel((offset++ << RK3588_ADDR_SHIFT) |
(RK3588_BURST_NUM << RK3588_BURST_SHIFT),
otp->base + RK3588_OTPC_AUTO_CTRL);
writel(RK3588_AUTO_EN, otp->base + RK3588_OTPC_AUTO_EN);
ret = rockchip_otp_wait_status(otp, RK3588_OTPC_INT_ST,
RK3588_RD_DONE);
- if (ret < 0) {
+ if (ret) {
dev_err(otp->dev, "timeout during read setup\n");
- goto read_end;
+ return ret;
}
- data = readl(otp->base + RK3588_OTPC_DOUT0);
- memcpy(&buf[i], &data, RK3588_NBYTES);
-
- i += RK3588_NBYTES;
- addr_start++;
+ *buf++ = readl(otp->base + RK3588_OTPC_DOUT0);
}
- memcpy(val, buf + offset % RK3588_NBYTES, bytes);
-
-read_end:
- kfree(buf);
-
return ret;
}
@@ -234,7 +214,7 @@ static int rockchip_otp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_otp *otp = context;
- int ret;
+ int ret, word_size;
if (!otp->data || !otp->data->reg_read)
return -EINVAL;
@@ -245,8 +225,34 @@ static int rockchip_otp_read(void *context, unsigned int offset,
return ret;
}
- ret = otp->data->reg_read(context, offset, val, bytes);
+ offset += otp->data->read_offset;
+ word_size = otp->data->word_size;
+
+ if (word_size > 1) {
+ unsigned int addr_start, addr_end;
+ size_t count;
+ u8 *buf;
+
+ addr_start = offset / word_size;
+ addr_end = DIV_ROUND_UP(offset + bytes, word_size);
+ count = addr_end - addr_start;
+
+ buf = kzalloc(array_size(count, word_size), GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = otp->data->reg_read(context, addr_start, buf, count);
+ if (!ret)
+ memcpy(val, buf + (offset % word_size), bytes);
+
+ kfree(buf);
+ } else {
+ ret = otp->data->reg_read(context, offset, val, bytes);
+ }
+err:
clk_bulk_disable_unprepare(otp->data->num_clks, otp->clks);
return ret;
@@ -259,7 +265,7 @@ static struct nvmem_config otp_config = {
.type = NVMEM_TYPE_OTP,
.read_only = true,
.stride = 1,
- .word_size = 1,
+ .word_size = sizeof(u8),
.reg_read = rockchip_otp_read,
};
@@ -277,6 +283,7 @@ static const struct rockchip_data px30_data = {
static const struct rockchip_data rk3576_data = {
.size = 0x100,
.read_offset = 0x700,
+ .word_size = sizeof(u32),
.clks = px30_otp_clocks,
.num_clks = ARRAY_SIZE(px30_otp_clocks),
.reg_read = rk3588_otp_read,
@@ -289,6 +296,7 @@ static const char * const rk3588_otp_clocks[] = {
static const struct rockchip_data rk3588_data = {
.size = 0x400,
.read_offset = 0xc00,
+ .word_size = sizeof(u32),
.clks = rk3588_otp_clocks,
.num_clks = ARRAY_SIZE(rk3588_otp_clocks),
.reg_read = rk3588_otp_read,
--
2.48.1
Powered by blists - more mailing lists