ARM: at91: sam9g45: shutdown ddr1 too when rebooting
authorJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Fri, 27 Sep 2013 06:37:59 +0000 (08:37 +0200)
committerOlof Johansson <olof@lixom.net>
Mon, 30 Sep 2013 16:58:44 +0000 (09:58 -0700)
Like we are doing on DDR0 we need to cleanly shutdown DDR1 if it is
used before rebooting.
If DDR1 is not initialized, we check it and avoid dereferencing its address.
Even by adding two more instructions, we are able to complete the procedure
within a single cache line.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
arch/arm/mach-at91/at91sam9g45_reset.S

index 721a1a34dd1d86027161e66b9cfaee7161ebfd03..c40c1e2ef80fa9d1485c06669afad3caf0ea17fc 100644 (file)
 #include "at91_rstc.h"
                        .arm
 
+/*
+ * at91_ramc_base is an array void*
+ * init at NULL if only one DDR controler is present in or DT
+ */
                        .globl  at91sam9g45_restart
 
 at91sam9g45_restart:
                        ldr     r5, =at91_ramc_base             @ preload constants
                        ldr     r0, [r5]
+                       ldr     r5, [r5, #4]                    @ ddr1
+                       cmp     r5, #0
                        ldr     r4, =at91_rstc_base
                        ldr     r1, [r4]
 
@@ -30,6 +36,8 @@ at91sam9g45_restart:
 
                        .balign 32                              @ align to cache line
 
+                       strne   r2, [r5, #AT91_DDRSDRC_RTR]     @ disable DDR1 access
+                       strne   r3, [r5, #AT91_DDRSDRC_LPR]     @ power down DDR1
                        str     r2, [r0, #AT91_DDRSDRC_RTR]     @ disable DDR0 access
                        str     r3, [r0, #AT91_DDRSDRC_LPR]     @ power down DDR0
                        str     r4, [r1, #AT91_RSTC_CR]         @ reset processor