@@ -19,6 +19,7 @@
#include <linux/percpu.h>
#include <linux/refcount.h>
#include <linux/slab.h>
+#include <linux/iopoll.h>
#include <linux/irqchip.h>
#include <linux/irqchip/arm-gic-common.h>
@@ -251,17 +252,16 @@ static inline void __iomem *gic_dist_base(struct irq_data *d)
static void gic_do_wait_for_rwp(void __iomem *base, u32 bit)
{
- u32 count = 1000000; /* 1s! */
+ u32 val;
+ int ret;
- while (readl_relaxed(base + GICD_CTLR) & bit) {
- count--;
- if (!count) {
- pr_err_ratelimited("RWP timeout, gone fishing\n");
- return;
- }
- cpu_relax();
- udelay(1);
- }
+ ret = readl_relaxed_poll_timeout_atomic(base + GICD_CTLR,
+ val,
+ !(val & bit),
+ 1,
+ USEC_PER_SEC);
+ if (ret == -ETIMEDOUT)
+ pr_err_ratelimited("RWP timeout, gone fishing\n");
}
/* Wait for completion of a distributor change */
@@ -279,8 +279,8 @@ static void gic_redist_wait_for_rwp(void)
static void gic_enable_redist(bool enable)
{
void __iomem *rbase;
- u32 count = 1000000; /* 1s! */
u32 val;
+ int ret;
if (gic_data.flags & FLAGS_WORKAROUND_GICR_WAKER_MSM8996)
return;
@@ -301,14 +301,12 @@ static void gic_enable_redist(bool enable)
return; /* No PM support in this redistributor */
}
- while (--count) {
- val = readl_relaxed(rbase + GICR_WAKER);
- if (enable ^ (bool)(val & GICR_WAKER_ChildrenAsleep))
- break;
- cpu_relax();
- udelay(1);
- }
- if (!count)
+ ret = readl_relaxed_poll_timeout_atomic(rbase + GICR_WAKER,
+ val,
+ enable ^ (bool)(val & GICR_WAKER_ChildrenAsleep),
+ 1,
+ USEC_PER_SEC);
+ if (ret == -ETIMEDOUT)
pr_err_ratelimited("redistributor failed to %s...\n",
enable ? "wakeup" : "sleep");
}
Kernel provide read*_poll_* API family to support looping based polling code pattern like below: while (...) { val = op(addr); condition = cond(val); if (condition) break; /* Maybe some timeout handling stuff */ cpu_relax(); udelay(); } As such, use readl_relaxed_poll_timeout_atomic() to implement atomic register polling logic in gic-v3. It's worth noting that this conversion would be impossilbe without support of commit 7349a69cf312 ("iopoll: Do not use timekeeping in read_poll_timeout_atomic()"), which remove time keeping code from read_poll_timeout_atomic(), reason below: Compared to other 'ordinary' device driver, IRQ chip driver is kinda special, whose initialization(via init_IRQ()) happens pretty early, even before timekeeping_init(). As a result, calling time keeping code in irq chip init code is bogus. Signed-off-by: Dawei Li <dawei.li@shingroup.cn> --- drivers/irqchip/irq-gic-v3.c | 36 +++++++++++++++++------------------- 1 file changed, 17 insertions(+), 19 deletions(-)