From 689f00fc7e65d90222890c2ac4225137002db846 Mon Sep 17 00:00:00 2001 From: Prabhakar Kushwaha Date: Sun, 29 Apr 2012 23:56:43 +0000 Subject: [PATCH] powerpc/85xx:Make debug exception vector accessible Debugging of e500 and e500v1 processer requires debug exception vecter (IVPR + IVOR15) to have valid and fetchable OP code. 1) While executing in translated space (AS=1), whenever a debug exception is generated, the MSR[DS/IS] gets cleared i.e. AS=0 and the processor tries to fetch an instruction from the debug exception vector (IVPR + IVOR15); since now we are in AS=0, the application needs to ensure the proper TLB configuration to have (IVOR + IVOR15) accessible from AS=0 also. Create a temporary TLB in AS0 to make sure debug exception verctor is accessible on debug exception. 2) Just after relocation in DDR, Make sure IVPR + IVOR15 points to valid opcode Signed-off-by: Radu Lazarescu Signed-off-by: Marius Grigoras Signed-off-by: Prabhakar Kushwaha --- arch/powerpc/cpu/mpc85xx/cpu_init_early.c | 32 +++++++++++- arch/powerpc/cpu/mpc85xx/start.S | 83 +++++++++++++++++++++++++++++-- 2 files changed, 109 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c index 091af7c..dacfdd1 100644 --- a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c +++ b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c @@ -1,5 +1,5 @@ /* - * Copyright 2009-2011 Freescale Semiconductor, Inc + * Copyright 2009-2012 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 @@ -53,6 +53,36 @@ void setup_ifc(void) asm volatile("isync;msync;tlbwe;isync"); +#if defined(CONFIG_SYS_PPC_E500_DEBUG_TLB) +/* + * TLB entry for debuggging in AS1 + * Create temporary TLB entry in AS0 to handle debug exception + * As on debug exception MSR is cleared i.e. Address space is changed + * to 0. A TLB entry (in AS0) is required to handle debug exception generated + * in AS1. + * + * TLB entry is created for IVPR + IVOR15 to map on valid OP code address + * bacause flash's physical address is going to change as + * CONFIG_SYS_FLASH_BASE_PHYS. + */ + _mas0 = MAS0_TLBSEL(1) | + MAS0_ESEL(CONFIG_SYS_PPC_E500_DEBUG_TLB); + _mas1 = MAS1_VALID | MAS1_TID(0) | MAS1_IPROT | + MAS1_TSIZE(BOOKE_PAGESZ_4M); + _mas2 = FSL_BOOKE_MAS2(CONFIG_SYS_TEXT_BASE, MAS2_I|MAS2_G); + _mas3 = FSL_BOOKE_MAS3(flash_phys, 0, MAS3_SW|MAS3_SR|MAS3_SX); + _mas7 = FSL_BOOKE_MAS7(flash_phys); + + mtspr(MAS0, _mas0); + mtspr(MAS1, _mas1); + mtspr(MAS2, _mas2); + mtspr(MAS3, _mas3); + mtspr(MAS7, _mas7); + + asm volatile("isync;msync;tlbwe;isync"); +#endif + + /* Change flash's physical address */ out_be32(&(ifc_regs->cspr_cs[0].cspr), CONFIG_SYS_CSPR0); out_be32(&(ifc_regs->csor_cs[0].csor), CONFIG_SYS_CSOR0); out_be32(&(ifc_regs->amask_cs[0].amask), CONFIG_SYS_AMASK0); diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S index 653e222..4267196 100644 --- a/arch/powerpc/cpu/mpc85xx/start.S +++ b/arch/powerpc/cpu/mpc85xx/start.S @@ -182,6 +182,72 @@ l2_disabled: andi. r1,r3,L1CSR0_DCE@l beq 2b +#if defined(CONFIG_SYS_PPC_E500_DEBUG_TLB) +/* + * TLB entry for debuggging in AS1 + * Create temporary TLB entry in AS0 to handle debug exception + * As on debug exception MSR is cleared i.e. Address space is changed + * to 0. A TLB entry (in AS0) is required to handle debug exception generated + * in AS1. + */ + + lis r6,FSL_BOOKE_MAS0(1, + CONFIG_SYS_PPC_E500_DEBUG_TLB, 0)@h + ori r6,r6,FSL_BOOKE_MAS0(1, + CONFIG_SYS_PPC_E500_DEBUG_TLB, 0)@l + +#if !defined(CONFIG_SYS_RAMBOOT) && !defined(CONFIG_SECURE_BOOT) +/* + * TLB entry is created for IVPR + IVOR15 to map on valid OP code address + * bacause flash's virtual address maps to 0xff800000 - 0xffffffff. + * and this window is outside of 4K boot window. + */ + lis r7,FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_4M)@h + ori r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_4M)@l + + lis r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE & 0xffc00000, + (MAS2_I|MAS2_G))@h + ori r8,r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE & 0xffc00000, + (MAS2_I|MAS2_G))@l + + /* 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) + lis r7,FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_1M)@h + ori r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 0, 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 +/* + * TLB entry is created for IVPR + IVOR15 to map on valid OP code address + * because "nexti" will resize TLB to 4K + */ + lis r7,FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_256K)@h + ori r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 0, BOOKE_PAGESZ_256K)@l + + lis r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE, (MAS2_I))@h + ori r8,r8,FSL_BOOKE_MAS2(CONFIG_SYS_MONITOR_BASE, + (MAS2_I))@l + lis r9,FSL_BOOKE_MAS3(CONFIG_SYS_MONITOR_BASE, 0, + (MAS3_SX|MAS3_SW|MAS3_SR))@h + ori r9,r9,FSL_BOOKE_MAS3(CONFIG_SYS_MONITOR_BASE, 0, + (MAS3_SX|MAS3_SW|MAS3_SR))@l +#endif + mtspr MAS0,r6 + mtspr MAS1,r7 + mtspr MAS2,r8 + mtspr MAS3,r9 + tlbwe + isync +#endif + /* * Ne need to setup interrupt vector for NAND SPL * because NAND SPL never compiles it. @@ -1375,17 +1441,24 @@ relocate_code: 7: sync /* Wait for all icbi to complete on bus */ isync - /* - * Re-point the IVPR at RAM - */ - mtspr IVPR,r10 - /* * We are done. Do not return, instead branch to second part of board * initialization, now running from RAM. */ addi r0,r10,in_ram - _start + _START_OFFSET + + /* + * As IVPR is going to point RAM address, + * Make sure IVOR15 has valid opcode to support debugger + */ + mtspr IVOR15,r0 + + /* + * Re-point the IVPR at RAM + */ + mtspr IVPR,r10 + mtlr r0 blr /* NEVER RETURNS! */ .globl in_ram