[PATCH 2/7] at91sam926x: lowlevel add external boot support
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Sat Dec 29 05:08:12 EST 2012
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
arch/arm/mach-at91/at91sam926x_lowlevel_init.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-at91/at91sam926x_lowlevel_init.c b/arch/arm/mach-at91/at91sam926x_lowlevel_init.c
index cfae982..4dec275 100644
--- a/arch/arm/mach-at91/at91sam926x_lowlevel_init.c
+++ b/arch/arm/mach-at91/at91sam926x_lowlevel_init.c
@@ -36,10 +36,19 @@ static void inline pmc_check_mckrdy(void)
} while (!(r & AT91_PMC_MCKRDY));
}
+static int inline running_in_sram(void)
+{
+ u32 addr = get_pc();
+
+ addr >>= 28;
+ return addr == 0;
+}
+
void __naked __bare_init reset(void)
{
u32 r;
int i;
+ int in_sram = running_in_sram();
common_reset();
@@ -74,7 +83,7 @@ void __naked __bare_init reset(void)
* PMC Check if the PLL is already initialized
*/
r = at91_pmc_read(AT91_PMC_MCKR);
- if (r & AT91_PMC_CSS)
+ if (r & AT91_PMC_CSS && !in_sram)
goto end;
/*
@@ -117,7 +126,7 @@ void __naked __bare_init reset(void)
* SDRAMC Check if Refresh Timer Counter is already initialized
*/
r = at91_sys_read(AT91_SDRAMC_TR);
- if (r)
+ if (r && !in_sram)
goto end;
/* SDRAMC_MR : Normal Mode */
@@ -170,6 +179,13 @@ void __naked __bare_init reset(void)
/* MATRIX_MCFG - REMAP all masters */
at91_sys_write(AT91_MATRIX_MCFG0, 0x1FF);
#endif
+ /*
+ * When boot from external boot
+ * we need to enable mck and ohter clock
+ * so enable all of them
+ * We will shutdown what we don't need later
+ */
+ at91_pmc_write(AT91_PMC_PCER, 0xffffffff);
end:
board_init_lowlevel_return();
--
1.7.10.4
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