From 9823f1a8463fb631fe965110fe19adeb3df239c4 Mon Sep 17 00:00:00 2001 From: Anders Larsen Date: Thu, 8 Apr 2010 11:48:16 +0100 Subject: ARM: 6043/1: AT91 slow-clock resume: Don't wait for a disabled PLL to lock at91 slow-clock resume: Don't wait for a disabled PLL to lock. We run into this problem with the PLLB on the at91: ohci-at91 disables the PLLB when going to suspend. The slowclock code however tries to do the same: It saves the PLLB register value and when restoring the value during resume, it waits for the PLLB to lock again. However the PLL will never lock and the loop would run into its timeout because the slowclock code just stored and restored an empty register. This fixes the problem by only restoring PLLA/PLLB when they were enabled at suspend time. Cc: Andrew Victor Signed-off-by: Anders Larsen Signed-off-by: Russell King --- arch/arm/mach-at91/pm_slowclock.S | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'arch') diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S index 987fab3d846a..9fcbd6ca0090 100644 --- a/arch/arm/mach-at91/pm_slowclock.S +++ b/arch/arm/mach-at91/pm_slowclock.S @@ -205,13 +205,25 @@ ENTRY(at91_slow_clock) ldr r3, .saved_pllbr str r3, [r1, #(AT91_CKGR_PLLBR - AT91_PMC)] + tst r3, #(AT91_PMC_MUL & 0xff0000) + bne 1f + tst r3, #(AT91_PMC_MUL & ~0xff0000) + beq 2f +1: wait_pllblock +2: /* Restore PLLA setting */ ldr r3, .saved_pllar str r3, [r1, #(AT91_CKGR_PLLAR - AT91_PMC)] + tst r3, #(AT91_PMC_MUL & 0xff0000) + bne 3f + tst r3, #(AT91_PMC_MUL & ~0xff0000) + beq 4f +3: wait_pllalock +4: #ifdef SLOWDOWN_MASTER_CLOCK /* -- cgit v1.2.3-59-g8ed1b