[U-Boot] [PATCH 1/2] ARM: atmel: spl: make initialization more stable
We need to make sure the main clock ready field in MCFR is set after switch to main crystal oscillator.
Signed-off-by: Bo Shen voice.shen@atmel.com ---
arch/arm/cpu/at91-common/spl.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/arm/cpu/at91-common/spl.c b/arch/arm/cpu/at91-common/spl.c index cbb5a52..1d7770e 100644 --- a/arch/arm/cpu/at91-common/spl.c +++ b/arch/arm/cpu/at91-common/spl.c @@ -50,6 +50,10 @@ static void switch_to_main_crystal_osc(void) while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCSELS)) ;
+ /* Wait until MAINRDY field is set to make sure main clock is stable */ + while (!(readl(&pmc->mcfr) & AT91_PMC_MAINRDY)) + ; + tmp = readl(&pmc->mor); tmp &= ~AT91_PMC_MOR_MOSCRCEN; tmp &= ~AT91_PMC_MOR_KEY(0xff);
The clock source for master clock can be slow clock, main clock, plla clock or upll clock. So, make the clock source selection field in mckr can be configured.
Signed-off-by: Bo Shen voice.shen@atmel.com ---
arch/arm/cpu/at91-common/spl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/arm/cpu/at91-common/spl.c b/arch/arm/cpu/at91-common/spl.c index 1d7770e..3ceb31b 100644 --- a/arch/arm/cpu/at91-common/spl.c +++ b/arch/arm/cpu/at91-common/spl.c @@ -76,10 +76,12 @@ void at91_mck_init(u32 mckr) u32 tmp;
tmp = readl(&pmc->mckr); - tmp &= ~(AT91_PMC_MCKR_PRES_MASK | + tmp &= ~(AT91_PMC_MCKR_CSS_MASK | + AT91_PMC_MCKR_PRES_MASK | AT91_PMC_MCKR_MDIV_MASK | AT91_PMC_MCKR_PLLADIV_2); - tmp |= mckr & (AT91_PMC_MCKR_PRES_MASK | + tmp |= mckr & (AT91_PMC_MCKR_CSS_MASK | + AT91_PMC_MCKR_PRES_MASK | AT91_PMC_MCKR_MDIV_MASK | AT91_PMC_MCKR_PLLADIV_2); writel(tmp, &pmc->mckr);
Dear Bo Shen,
Bo Shen voice.shen@atmel.com writes:
The clock source for master clock can be slow clock, main clock, plla clock or upll clock. So, make the clock source selection field in mckr can be configured.
Signed-off-by: Bo Shen voice.shen@atmel.com
arch/arm/cpu/at91-common/spl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
applied to u-boot-atmel/master, thanks!
Best regards, Andreas Bießmann
Dear Bo Shen,
Bo Shen voice.shen@atmel.com writes:
We need to make sure the main clock ready field in MCFR is set after switch to main crystal oscillator.
Signed-off-by: Bo Shen voice.shen@atmel.com
arch/arm/cpu/at91-common/spl.c | 4 ++++ 1 file changed, 4 insertions(+)
applied to u-boot-atmel/master, thanks!
Best regards, Andreas Bießmann
participants (2)
-
Andreas Bießmann -
Bo Shen