diff options
Diffstat (limited to 'arch/arm/mach-at91/pm_suspend.S')
| -rw-r--r-- | arch/arm/mach-at91/pm_suspend.S | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S index bfe1c4d06901..8b18cad1dcf5 100644 --- a/arch/arm/mach-at91/pm_suspend.S +++ b/arch/arm/mach-at91/pm_suspend.S @@ -197,8 +197,26 @@ ENDPROC(at91_backup_mode) .macro at91_pm_ulp1_mode ldr pmc, .pmc_base - /* Switch the main clock source to 12-MHz RC oscillator */ + /* Save RC oscillator state and check if it is enabled. */ + ldr tmp1, [pmc, #AT91_PMC_SR] + str tmp1, .saved_osc_status + tst tmp1, #AT91_PMC_MOSCRCS + bne 2f + + /* Enable RC oscillator */ ldr tmp1, [pmc, #AT91_CKGR_MOR] + orr tmp1, tmp1, #AT91_PMC_MOSCRCEN + bic tmp1, tmp1, #AT91_PMC_KEY_MASK + orr tmp1, tmp1, #AT91_PMC_KEY + str tmp1, [pmc, #AT91_CKGR_MOR] + + /* Wait main RC stabilization */ +1: ldr tmp1, [pmc, #AT91_PMC_SR] + tst tmp1, #AT91_PMC_MOSCRCS + beq 1b + + /* Switch the main clock source to 12-MHz RC oscillator */ +2: ldr tmp1, [pmc, #AT91_CKGR_MOR] bic tmp1, tmp1, #AT91_PMC_MOSCSEL bic tmp1, tmp1, #AT91_PMC_KEY_MASK orr tmp1, tmp1, #AT91_PMC_KEY @@ -262,6 +280,25 @@ ENDPROC(at91_backup_mode) str tmp1, [pmc, #AT91_PMC_MCKR] wait_mckrdy + + /* Restore RC oscillator state */ + ldr tmp1, .saved_osc_status + tst tmp1, #AT91_PMC_MOSCRCS + bne 3f + + /* Disable RC oscillator */ + ldr tmp1, [pmc, #AT91_CKGR_MOR] + bic tmp1, tmp1, #AT91_PMC_MOSCRCEN + bic tmp1, tmp1, #AT91_PMC_KEY_MASK + orr tmp1, tmp1, #AT91_PMC_KEY + str tmp1, [pmc, #AT91_CKGR_MOR] + + /* Wait RC oscillator disable done */ +4: ldr tmp1, [pmc, #AT91_PMC_SR] + tst tmp1, #AT91_PMC_MOSCRCS + bne 4b + +3: .endm ENTRY(at91_ulp_mode) @@ -475,6 +512,8 @@ ENDPROC(at91_sramc_self_refresh) .word 0 .saved_sam9_mdr1: .word 0 +.saved_osc_status: + .word 0 ENTRY(at91_pm_suspend_in_sram_sz) .word .-at91_pm_suspend_in_sram |