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    SubjectRe: [PATCH 2/2] AT91 slow-clock resume: don't restore the PLL settings when the PLL was off
    hi Anders,

    > 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.
    > Signed-off-by: Anders Larsen <>
    > Cc: Andrew Victor <>
    > Cc: Julien Langer <>

    > +       tst     r3, #(AT91_PMC_MUL &  0xff0000)
    > +       bne     1f
    > +       tst     r3, #(AT91_PMC_MUL & ~0xff0000)
    > +       beq     2f
    > +1:
    >        wait_pllblock
    > +2:

    AT91_PMC_MUL is 11 bits (so 0x7ff0000)

    Is the mask (0xff0000) correct in the above code?
    It looks like wait_pllblock will be skipped if the MUL field is set to
    0x100, 0x200, 0x300, etc.

    Andrew Victor
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      Last update: 2010-04-13 10:17    [W:0.029 / U:1.468 seconds]
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