powerpc/p4080: Add support for secure boot flow

Pre u-boot Flow:
1. User loads the u-boot image in flash
2. PBL/Configuration word is used to create LAW for Flash at 0xc0000000
   (Please note that ISBC expects all these addresses, images to be
    validated, entry point etc within 0 - 3.5G range)
3. ISBC validates the u-boot image, and passes control to u-boot
   at 0xcffffffc.

Changes in u-boot:
1. Temporarily map CONFIG_SYS_MONITOR_BASE to the 1M
   CONFIG_SYS_PBI_FLASH_WINDOW in AS=1.
   (The CONFIG_SYS_PBI_FLASH_WINDOW is the address map for the flash
    created by PBL/configuration word within 0 - 3.5G memory range. The
    u-boot image at this address has been validated by ISBC code)
2. Remove TLB entries for 0 - 3.5G created by ISBC code
3. Remove the LAW entry for the CONFIG_SYS_PBI_FLASH_WINDOW created by
   PBL/configuration word after switch to AS = 1

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Kuldip Giroh <kuldip.giroh@freescale.com>
Acked-by: Wood Scott-B07421 <B07421@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

3 files changed, 73 insertions, 3 deletions

diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init.c b/arch/powerpc/cpu/mpc85xx/cpu_init.c
index 27f836c3d2..e2c5b6fc3e 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu_init.c
@@ -226,7 +226,9 @@ void cpu_init_f (void)
 #ifdef CONFIG_SYS_DCSRBAR_PHYS
 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
 #endif
-
+#if defined(CONFIG_SECURE_BOOT)
+	struct law_entry law;
+#endif
 #ifdef CONFIG_MPC8548
 	ccsr_local_ecm_t *ecm = (void *)(CONFIG_SYS_MPC85xx_ECM_ADDR);
 	uint svr = get_svr();
@@ -244,6 +246,13 @@ void cpu_init_f (void)
 	disable_tlb(14);
 	disable_tlb(15);
 
+#if defined(CONFIG_SECURE_BOOT)
+	/* Disable the LAW created for NOR flash by the PBI commands */
+	law = find_law(CONFIG_SYS_PBI_FLASH_BASE);
+	if (law.index != -1)
+		disable_law(law.index);
+#endif
+
 #ifdef CONFIG_CPM2
 	config_8560_ioports((ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR);
 #endif
diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
index a04f5c101f..4ef3c9a8a5 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009 Freescale Semiconductor, Inc
+ * Copyright 2009-2011 Freescale Semiconductor, Inc
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -149,5 +149,13 @@ void cpu_init_early_f(void)
 #endif
 
 	invalidate_tlb(1);
+
+#if defined(CONFIG_SECURE_BOOT)
+	/* Disable the TLBs created by ISBC */
+	for (i = CONFIG_SYS_ISBC_START_TLB;
+	     i < CONFIG_SYS_ISBC_START_TLB + CONFIG_SYS_ISBC_NUM_TLBS; i++)
+			disable_tlb(i);
+#endif
+
 	init_tlbs();
 }
diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S
index d89d18ce81..5e0d78d006 100644
--- a/arch/powerpc/cpu/mpc85xx/start.S
+++ b/arch/powerpc/cpu/mpc85xx/start.S
@@ -83,6 +83,45 @@
 
 _start_e500:
 
+#if defined(CONFIG_SECURE_BOOT) && defined(CONFIG_E500MC)
+	/* ISBC uses L2 as stack.
+	 * Disable L2 cache here so that u-boot can enable it later
+	 * as part of it's normal flow
+	*/
+
+	/* Check if L2 is enabled */
+	mfspr	r3, SPRN_L2CSR0
+	lis	r2, L2CSR0_L2E@h
+	ori	r2, r2, L2CSR0_L2E@l
+	and.	r4, r3, r2
+	beq	l2_disabled
+
+	mfspr r3, SPRN_L2CSR0
+	/* Flush L2 cache */
+	lis     r2,(L2CSR0_L2FL)@h
+	ori     r2, r2, (L2CSR0_L2FL)@l
+	or      r3, r2, r3
+	sync
+	isync
+	mtspr   SPRN_L2CSR0,r3
+	isync
+1:
+	mfspr r3, SPRN_L2CSR0
+	and. r1, r3, r2
+	bne 1b
+
+	mfspr r3, SPRN_L2CSR0
+	lis r2, L2CSR0_L2E@h
+	ori r2, r2, L2CSR0_L2E@l
+	andc r4, r3, r2
+	sync
+	isync
+	mtspr SPRN_L2CSR0,r4
+	isync
+
+l2_disabled:
+#endif
+
 /* clear registers/arrays not reset by hardware */
 
 	/* L1 */
@@ -516,7 +555,7 @@ create_init_ram_area:
 	lis     r6,FSL_BOOKE_MAS0(1, 15, 0)@h
 	ori     r6,r6,FSL_BOOKE_MAS0(1, 15, 0)@l
 
-#ifndef CONFIG_SYS_RAMBOOT
+#if !defined(CONFIG_SYS_RAMBOOT) && !defined(CONFIG_SECURE_BOOT)
 	/* create a temp mapping in AS=1 to the 4M boot window */
 	lis     r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_4M)@h
 	ori     r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_4M)@l
@@ -527,6 +566,20 @@ create_init_ram_area:
 	/* The 85xx has the default boot window 0xff800000 - 0xffffffff */
 	lis     r9,FSL_BOOKE_MAS3(0xffc00000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@h
 	ori     r9,r9,FSL_BOOKE_MAS3(0xffc00000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@l
+#elif !defined(CONFIG_SYS_RAMBOOT) && defined(CONFIG_SECURE_BOOT)
+	/* create a temp mapping in AS = 1 for Flash mapping
+	 * created by PBL for ISBC code
+	*/
+	lis     r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_1M)@h
+	ori     r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_1M)@l
+
+	lis     r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE, (MAS2_I|MAS2_G))@h
+	ori     r8,r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE, (MAS2_I|MAS2_G))@l
+
+	lis     r9,FSL_BOOKE_MAS3(CONFIG_SYS_PBI_FLASH_WINDOW, 0,
+						(MAS3_SX|MAS3_SW|MAS3_SR))@h
+	ori     r9,r9,FSL_BOOKE_MAS3(CONFIG_SYS_PBI_FLASH_WINDOW, 0,
+						(MAS3_SX|MAS3_SW|MAS3_SR))@l
 #else
 	/*
 	 * create a temp mapping in AS=1 to the 1M CONFIG_SYS_MONITOR_BASE space, the main