[U-Boot] [PATCH 1/2 v2] 85xx: CONFIG_MP Boot Page Translation update
Peter Tyser
ptyser at xes-inc.com
Thu Aug 6 00:23:43 CEST 2009
Previously, when CONFIG_MP was defined Boot Page Translation was
unconditionally enabled and secondary cores were put in a spin loop at
address 0xfffff000. The 0xfffffxxx address range (ie the Boot Page) was
being remapped to SDRAM via the BPTR register.
This change puts secondary cores into spin loops at their 'true' address
in SDRAM and doesn't require Boot Page Translation to always be enabled.
The main advantage of this change is that Boot Page Translation can be
disabled after the secondary cores are brought up which allows the
memory region at 0xfffffxxx to be used for other peripherals, etc.
By default, Boot Page Translation remains enabled while U-Boot executes.
A new CONFIG_MPC8xxx_DISABLE_BPTR define has been added which causes
Boot Page Translation to be disabled for those boards which wish to use
the 0xfffffxxx address range as part of their normal memory map.
Signed-off-by: Peter Tyser <ptyser at xes-inc.com>
---
Changes since v1:
- Use clrbits_be32() instead of in/out_be32()
This is very similar to "85xx: Fix mapping of 0xfffffxxx when CONFIG_MP"
The 2 differences are:
- Boot page translation is only disabled when CONFIG_MPC8xxx_DISABLT_BPTR
is defined.
- Instead of zeroing out BPTR when disabling translation, this
patch only disables translation, but maintins the translation
address. This should make it easier to properly re-enable
translation if need be.
cpu/mpc85xx/mp.c | 22 ++++++++++++++++++++--
cpu/mpc85xx/release.S | 30 +++++++++++++++++++++++++-----
2 files changed, 45 insertions(+), 7 deletions(-)
diff --git a/cpu/mpc85xx/mp.c b/cpu/mpc85xx/mp.c
index 76f02a4..53fc3be 100644
--- a/cpu/mpc85xx/mp.c
+++ b/cpu/mpc85xx/mp.c
@@ -129,7 +129,7 @@ ulong get_spin_addr(void)
ulong addr =
(ulong)&__spin_table - (ulong)&__secondary_start_page;
- addr += 0xfffff000;
+ addr += determine_mp_bootpg();
return addr;
}
@@ -137,7 +137,8 @@ ulong get_spin_addr(void)
static void pq3_mp_up(unsigned long bootpg)
{
u32 up, cpu_up_mask, whoami;
- u32 *table = (u32 *)get_spin_addr();
+ /* The table is at 0xfffffxxx due to boot page translation below */
+ u32 *table = (u32 *)(0xfffff000 | get_spin_addr());
volatile u32 bpcr;
volatile ccsr_local_ecm_t *ecm = (void *)(CONFIG_SYS_MPC85xx_ECM_ADDR);
volatile ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
@@ -146,6 +147,8 @@ static void pq3_mp_up(unsigned long bootpg)
int timeout = 10;
whoami = in_be32(&pic->whoami);
+
+ /* Translate 0xfffffxxx 'bootpg' address range to SDRAM */
out_be32(&ecm->bptr, 0x80000000 | (bootpg >> 12));
/* disable time base at the platform */
@@ -194,6 +197,17 @@ static void pq3_mp_up(unsigned long bootpg)
devdisr &= ~(MPC85xx_DEVDISR_TB0 | MPC85xx_DEVDISR_TB1);
out_be32(&gur->devdisr, devdisr);
+
+#ifdef CONFIG_MPC8xxx_DISABLE_BPTR
+ /*
+ * Disabling Boot Page Translation allows the memory region 0xfffff000
+ * to 0xffffffff to be used normally. Leaving Boot Page Translation
+ * enabled remaps 0xfffff000 to SDRAM which makes that memory region
+ * unusable for normal operation but it does allow OSes to easily
+ * reset a processor core to put it back into U-Boot's spinloop.
+ */
+ clrbits_be32(&ecm->bptr, 0x80000000);
+#endif
}
void cpu_mp_lmb_reserve(struct lmb *lmb)
@@ -206,9 +220,13 @@ void cpu_mp_lmb_reserve(struct lmb *lmb)
void setup_mp(void)
{
extern ulong __secondary_start_page;
+ extern ulong __bootpg_addr;
ulong fixup = (ulong)&__secondary_start_page;
u32 bootpg = determine_mp_bootpg();
+ /* Store the bootpg's SDRAM address for use by secondary CPU cores */
+ __bootpg_addr = bootpg;
+
memcpy((void *)bootpg, (void *)fixup, 4096);
flush_cache(bootpg, 4096);
diff --git a/cpu/mpc85xx/release.S b/cpu/mpc85xx/release.S
index fbefc2c..6799633 100644
--- a/cpu/mpc85xx/release.S
+++ b/cpu/mpc85xx/release.S
@@ -114,23 +114,38 @@ __secondary_start_page:
stw r3,ENTRY_R6_UPPER(r10)
stw r3,ENTRY_R6_LOWER(r10)
+ /* load r13 with the address of the 'bootpg' in SDRAM */
+ lis r13,toreset(__bootpg_addr)@h
+ ori r13,r13,toreset(__bootpg_addr)@l
+ lwz r13,0(r13)
+
/* setup mapping for AS = 1, and jump there */
lis r11,(MAS0_TLBSEL(1)|MAS0_ESEL(1))@h
mtspr SPRN_MAS0,r11
lis r11,(MAS1_VALID|MAS1_IPROT)@h
ori r11,r11,(MAS1_TS|MAS1_TSIZE(BOOKE_PAGESZ_4K))@l
mtspr SPRN_MAS1,r11
- lis r11,(0xfffff000|MAS2_I)@h
- ori r11,r11,(0xfffff000|MAS2_I)@l
+ oris r11,r13,(MAS2_I)@h
+ ori r11,r13,(MAS2_I)@l
mtspr SPRN_MAS2,r11
- lis r11,(0xfffff000|MAS3_SX|MAS3_SW|MAS3_SR)@h
- ori r11,r11,(0xfffff000|MAS3_SX|MAS3_SW|MAS3_SR)@l
+ oris r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@h
+ ori r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@l
mtspr SPRN_MAS3,r11
tlbwe
bl 1f
1: mflr r11
- addi r11,r11,28
+ /*
+ * OR in 0xfff to create a mask of the bootpg SDRAM address. We use
+ * this mask to fixup the cpu spin table and the address that we want
+ * to jump to, eg change them from 0xfffffxxx to 0x7ffffxxx if the
+ * bootpg is at 0x7ffff000 in SDRAM.
+ */
+ ori r13,r13,0xfff
+ and r11, r11, r13
+ and r10, r10, r13
+
+ addi r11,r11,(2f-1b)
mfmsr r13
ori r12,r13,MSR_IS|MSR_DS at l
@@ -200,6 +215,11 @@ __secondary_start_page:
mtspr SPRN_SRR1,r13
rfi
+ /* Allocate some space for the SDRAM address of the bootpg */
+ .globl __bootpg_addr
+__bootpg_addr:
+ .long 0
+
.align L1_CACHE_SHIFT
.globl __spin_table
__spin_table:
--
1.6.2.1
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