Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

ARM: shmobile: R-Car: Break infinite loop

Browse source 
rcar_sysc_update() loops (with interrupts disabled and while holding a
spinlock) until submitting a power shutoff or resume request fails, or
until the submitted request was accepted.
If none of these conditions becomes true, this forms an infinite loop.

Put a limit on the maximum number of loop iterations, and add a small
delay to each iteration, to fix this.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
This commit is contained in:
Geert Uytterhoeven 2015-06-04 20:22:29 +02:00 • committed by Simon Horman
parent 6fd2242e60
commit 2f575fcff1
1 changed files with 14 additions and 2 deletions

16
arch/arm/mach-shmobile/pm-rcar.c
View file

@ -42,6 +42,9 @@
#define SYSCSR_RETRIES 100
#define SYSCSR_DELAY_US 1
#define PWRER_RETRIES 100
#define PWRER_DELAY_US 1
#define SYSCISR_RETRIES 1000
#define SYSCISR_DELAY_US 1
@ -95,14 +98,23 @@ static int rcar_sysc_update(struct rcar_sysc_ch *sysc_ch,
iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);
/* Submit power shutoff or resume request until it was accepted */
do {
for (k = 0; k < PWRER_RETRIES; k++) {
ret = on_off_fn(sysc_ch);
if (ret)
goto out;
status = ioread32(rcar_sysc_base +
sysc_ch->chan_offs + PWRER_OFFS);
} while (status & chan_mask);
if (!(status & chan_mask))
break;
udelay(PWRER_DELAY_US);
}
if (k == PWRER_RETRIES) {
ret = -EIO;
goto out;
}
/* Wait until the power shutoff or resume request has completed * */
for (k = 0; k < SYSCISR_RETRIES; k++) {