[PATCH v3 06/11] reset: starfive: jh71x0: Use 32bit I/O on 32bit registers

Hal Feng
2022-12-20T00:57:14Z

From: Emil Renner Berthing <kernel@esmil.dk>

We currently use 64bit I/O on the 32bit registers. This works because
there are an even number of assert and status registers, so they're only
ever accessed in pairs on 64bit boundaries.

There are however other reset controllers for audio and video on the
JH7100 SoC with only one status register that isn't 64bit aligned so
64bit I/O results in an unaligned access exception.

Switch to 32bit I/O in preparation for supporting these resets too.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
---
.../reset/starfive/reset-starfive-jh7100.c | 14 ++++-----
.../reset/starfive/reset-starfive-jh71x0.c | 31 +++++++++----------
.../reset/starfive/reset-starfive-jh71x0.h | 2 +-
3 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/drivers/reset/starfive/reset-starfive-jh7100.c b/drivers/reset/starfive/reset-starfive-jh7100.c
index 5f06e5ae3346..2a56f7fd4ba7 100644
--- a/drivers/reset/starfive/reset-starfive-jh7100.c
+++ b/drivers/reset/starfive/reset-starfive-jh7100.c
@@ -30,16 +30,16 @@
* lines don't though, so store the expected value of the status registers when
* all lines are asserted.
*/
-static const u64 jh7100_reset_asserted[2] = {
+static const u32 jh7100_reset_asserted[4] = {
/* STATUS0 */
- BIT_ULL_MASK(JH7100_RST_U74) |
- BIT_ULL_MASK(JH7100_RST_VP6_DRESET) |
- BIT_ULL_MASK(JH7100_RST_VP6_BRESET) |
+ BIT(JH7100_RST_U74 % 32) |
+ BIT(JH7100_RST_VP6_DRESET % 32) |
+ BIT(JH7100_RST_VP6_BRESET % 32),
/* STATUS1 */
- BIT_ULL_MASK(JH7100_RST_HIFI4_DRESET) |
- BIT_ULL_MASK(JH7100_RST_HIFI4_BRESET),
+ BIT(JH7100_RST_HIFI4_DRESET % 32) |
+ BIT(JH7100_RST_HIFI4_BRESET % 32),
/* STATUS2 */
- BIT_ULL_MASK(JH7100_RST_E24) |
+ BIT(JH7100_RST_E24 % 32),
/* STATUS3 */
0,
};
diff --git a/drivers/reset/starfive/reset-starfive-jh71x0.c b/drivers/reset/starfive/reset-starfive-jh71x0.c
index 1f201c612583..c62d0c309c62 100644
--- a/drivers/reset/starfive/reset-starfive-jh71x0.c
+++ b/drivers/reset/starfive/reset-starfive-jh71x0.c
@@ -8,7 +8,6 @@
#include <linux/bitmap.h>
#include <linux/device.h>
#include <linux/io.h>
-#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/iopoll.h>
#include <linux/reset-controller.h>
#include <linux/spinlock.h>
@@ -19,7 +18,7 @@ struct jh71x0_reset {
spinlock_t lock;
void __iomem *assert;
void __iomem *status;
- const u64 *asserted;
+ const u32 *asserted;
};

static inline struct jh71x0_reset *
@@ -32,12 +31,12 @@ static int jh71x0_reset_update(struct reset_controller_dev *rcdev,
unsigned long id, bool assert)
{
struct jh71x0_reset *data = jh71x0_reset_from(rcdev);
- unsigned long offset = BIT_ULL_WORD(id);
- u64 mask = BIT_ULL_MASK(id);
- void __iomem *reg_assert = data->assert + offset * sizeof(u64);
- void __iomem *reg_status = data->status + offset * sizeof(u64);
- u64 done = data->asserted ? data->asserted[offset] & mask : 0;
- u64 value;
+ unsigned long offset = id / 32;
+ u32 mask = BIT(id % 32);
+ void __iomem *reg_assert = data->assert + offset * sizeof(u32);
+ void __iomem *reg_status = data->status + offset * sizeof(u32);
+ u32 done = data->asserted ? data->asserted[offset] & mask : 0;
+ u32 value;
unsigned long flags;
int ret;

@@ -46,15 +45,15 @@ static int jh71x0_reset_update(struct reset_controller_dev *rcdev,

spin_lock_irqsave(&data->lock, flags);

- value = readq(reg_assert);
+ value = readl(reg_assert);
if (assert)
value |= mask;
else
value &= ~mask;
- writeq(value, reg_assert);
+ writel(value, reg_assert);

/* if the associated clock is gated, deasserting might otherwise hang forever */
- ret = readq_poll_timeout_atomic(reg_status, value, (value & mask) == done, 0, 1000);
+ ret = readl_poll_timeout_atomic(reg_status, value, (value & mask) == done, 0, 1000);

spin_unlock_irqrestore(&data->lock, flags);
return ret;
@@ -88,10 +87,10 @@ static int jh71x0_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct jh71x0_reset *data = jh71x0_reset_from(rcdev);
- unsigned long offset = BIT_ULL_WORD(id);
- u64 mask = BIT_ULL_MASK(id);
- void __iomem *reg_status = data->status + offset * sizeof(u64);
- u64 value = readq(reg_status);
+ unsigned long offset = id / 32;
+ u32 mask = BIT(id % 32);
+ void __iomem *reg_status = data->status + offset * sizeof(u32);
+ u32 value = readl(reg_status);

return !((value ^ data->asserted[offset]) & mask);
}
@@ -105,7 +104,7 @@ static const struct reset_control_ops jh71x0_reset_ops = {

int reset_starfive_jh71x0_register(struct device *dev, struct device_node *of_node,
void __iomem *assert, void __iomem *status,
- const u64 *asserted, unsigned int nr_resets,
+ const u32 *asserted, unsigned int nr_resets,
struct module *owner)
{
struct jh71x0_reset *data;
diff --git a/drivers/reset/starfive/reset-starfive-jh71x0.h b/drivers/reset/starfive/reset-starfive-jh71x0.h
index ac9e80dd3f59..db7d39a87f87 100644
--- a/drivers/reset/starfive/reset-starfive-jh71x0.h
+++ b/drivers/reset/starfive/reset-starfive-jh71x0.h
@@ -8,7 +8,7 @@

int reset_starfive_jh71x0_register(struct device *dev, struct device_node *of_node,
void __iomem *assert, void __iomem *status,
- const u64 *asserted, unsigned int nr_resets,
+ const u32 *asserted, unsigned int nr_resets,
struct module *owner);

#endif /* __RESET_STARFIVE_JH71X0_H */
--
2.38.1