85xx: MP Boot Page Translation update

This change has 3 goals:
- Have secondary cores be released into spin loops at their 'true'
  address in SDRAM.  Previously, secondary cores were put into spin
  loops in the 0xfffffxxx address range which required that boot page
  translation was always enabled while cores were in their spin loops.

- Allow the TLB window that the primary core uses to access the
  secondary cores boot page to be placed at any address.  Previously, a
  TLB window at 0xfffff000 was always used to access the seconary cores'
  boot page.  This TLB address requirement overlapped with other
  peripherals on some boards (eg XPedite5370).  By default, the boot
  page TLB will still use the 0xfffffxxx address range, but this can be
  overridden on a board-by-board basis by defining a custom
  CONFIG_BPTR_VIRT_ADDR.  Note that the TLB used to map the boot page
  remains in use while U-Boot executes.  Previously it was only
  temporarily used, then restored to its initial value.

- Allow Boot Page Translation to be disabled on bootup.  Previously,
  Boot Page Translation was always left enabled after secondary cores
  were brought out of reset.  This caused the 0xfffffxxx address range
  to somewhat "magically" be translated to an address in SDRAM.  Some
  boards may not want this oddity in their memory map, so defining
  CONFIG_MPC8xxx_DISABLE_BPTR will turn off Boot Page Translation after
  the secondary cores are initialized.

These changes are only applicable to 85xx boards with CONFIG_MP defined.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 29 insertions, 5 deletions

diff --git a/cpu/mpc85xx/release.S b/cpu/mpc85xx/release.S
index ecbd0d5..a1ae78a 100644
--- a/cpu/mpc85xx/release.S
+++ b/cpu/mpc85xx/release.S
@@ -138,23 +138,38 @@ __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@l
 
@@ -227,6 +242,15 @@ __secondary_start_page:
 	mtspr	SPRN_SRR1,r13
 	rfi
 
+	/*
+	 * Allocate some space for the SDRAM address of the bootpg.
+	 * This variable has to be in the boot page so that it can
+	 * be accessed by secondary cores when they come out of reset.
+	 */
+	.globl __bootpg_addr
+__bootpg_addr:
+	.long	0
+
 	.align L1_CACHE_SHIFT
 	.globl __spin_table
 __spin_table: