diff options
Diffstat (limited to 'target/linux/bcm53xx/patches-3.18/300-ARM-BCM5301X-Disable-MMU-and-Dcache-for-decompression.patch')
| -rw-r--r-- | target/linux/bcm53xx/patches-3.18/300-ARM-BCM5301X-Disable-MMU-and-Dcache-for-decompression.patch | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/target/linux/bcm53xx/patches-3.18/300-ARM-BCM5301X-Disable-MMU-and-Dcache-for-decompression.patch b/target/linux/bcm53xx/patches-3.18/300-ARM-BCM5301X-Disable-MMU-and-Dcache-for-decompression.patch new file mode 100644 index 0000000..56db9c1 --- /dev/null +++ b/target/linux/bcm53xx/patches-3.18/300-ARM-BCM5301X-Disable-MMU-and-Dcache-for-decompression.patch @@ -0,0 +1,195 @@ +From 26023cdfacaf116545b1087b9d1fe50dc6fbda10 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com> +Date: Wed, 24 Sep 2014 22:14:07 +0200 +Subject: [PATCH] ARM: BCM5301X: Disable MMU and Dcache for decompression +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Without this fix kernel was randomly hanging in ~25% of tries during +early init. Hangs used to happen at random places in the start_kernel. + +Signed-off-by: Rafał Miłecki <zajec5@gmail.com> +--- + arch/arm/boot/compressed/Makefile | 5 + + arch/arm/boot/compressed/head-bcm_5301x-mpcore.S | 37 +++++++ + arch/arm/boot/compressed/mpcore_cache.S | 118 +++++++++++++++++++++++ + 3 files changed, 160 insertions(+) + create mode 100644 arch/arm/boot/compressed/head-bcm_5301x-mpcore.S + create mode 100644 arch/arm/boot/compressed/mpcore_cache.S + +--- a/arch/arm/boot/compressed/Makefile ++++ b/arch/arm/boot/compressed/Makefile +@@ -46,6 +46,11 @@ ifeq ($(CONFIG_ARCH_ACORN),y) + OBJS += ll_char_wr.o font.o + endif + ++ifeq ($(CONFIG_ARCH_BCM_5301X),y) ++OBJS += head-bcm_5301x-mpcore.o ++OBJS += mpcore_cache.o ++endif ++ + ifeq ($(CONFIG_ARCH_SA1100),y) + OBJS += head-sa1100.o + endif +--- /dev/null ++++ b/arch/arm/boot/compressed/head-bcm_5301x-mpcore.S +@@ -0,0 +1,37 @@ ++/* ++ * ++ * Platform specific tweaks. This is merged into head.S by the linker. ++ * ++ */ ++ ++#include <linux/linkage.h> ++#include <asm/assembler.h> ++#include <asm/cp15.h> ++ ++ .section ".start", "ax" ++ ++/* ++ * This code section is spliced into the head code by the linker ++ */ ++ ++__plat_uncompress_start: ++ ++ @ Preserve r8/r7 i.e. kernel entry values ++ mov r12, r8 ++ ++ @ Clear MMU enable and Dcache enable bits ++ mrc p15, 0, r0, c1, c0, 0 @ Read SCTLR ++ bic r0, #CR_C|CR_M ++ mcr p15, 0, r0, c1, c0, 0 @ Write SCTLR ++ nop ++ ++ @ Call the cache invalidation routine ++ bl v7_all_dcache_invalidate ++ nop ++ mov r0,#0 ++ ldr r3, =0x19022000 @ L2 cache controller, control reg ++ str r0, [r3, #0x100] @ Disable L2 cache ++ nop ++ ++ @ Restore ++ mov r8, r12 +--- /dev/null ++++ b/arch/arm/boot/compressed/mpcore_cache.S +@@ -0,0 +1,118 @@ ++/***************************************************************************** ++* Copyright 2003 - 2008 Broadcom Corporation. All rights reserved. ++* ++* Unless you and Broadcom execute a separate written software license ++* agreement governing use of this software, this software is licensed to you ++* under the terms of the GNU General Public License version 2, available at ++* http://www.broadcom.com/licenses/GPLv2.php (the "GPL"). ++* ++* Notwithstanding the above, under no circumstances may you combine this ++* software in any way with any other Broadcom software provided under a ++* license other than the GPL, without Broadcom's express prior written ++* consent. ++*****************************************************************************/ ++ ++#include <linux/linkage.h> ++#include <linux/init.h> ++ ++ __INIT ++ ++/* ++ * v7_l1_cache_invalidate ++ * ++ * Invalidate contents of L1 cache without flushing its contents ++ * into outer cache and memory. This is needed when the contents ++ * of the cache are unpredictable after power-up. ++ * ++ * corrupts r0-r6 ++ */ ++ ++ENTRY(v7_l1_cache_invalidate) ++ mov r0, #0 ++ mcr p15, 2, r0, c0, c0, 0 @ set cache level to 1 ++ mrc p15, 1, r0, c0, c0, 0 @ read CLIDR ++ ++ ldr r1, =0x7fff ++ and r2, r1, r0, lsr #13 @ get max # of index size ++ ++ ldr r1, =0x3ff ++ and r3, r1, r0, lsr #3 @ NumWays - 1 ++ add r2, r2, #1 @ NumSets ++ ++ and r0, r0, #0x7 ++ add r0, r0, #4 @ SetShift ++ ++ clz r1, r3 @ WayShift ++ add r4, r3, #1 @ NumWays ++1: sub r2, r2, #1 @ NumSets-- ++ mov r3, r4 @ Temp = NumWays ++2: subs r3, r3, #1 @ Temp-- ++ mov r5, r3, lsl r1 ++ mov r6, r2, lsl r0 ++ orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift) ++ mcr p15, 0, r5, c7, c6, 2 @ Invalidate line ++ bgt 2b ++ cmp r2, #0 ++ bgt 1b ++ dsb ++ mov r0,#0 ++ mcr p15,0,r0,c7,c5,0 /* Invalidate icache */ ++ isb ++ mov pc, lr ++ENDPROC(v7_l1_cache_invalidate) ++ ++/* ++ * v7_all_dcache_invalidate ++ * ++ * Invalidate without flushing the contents of all cache levels ++ * accesible by the current processor core. ++ * This is useful when the contents of cache memory are undetermined ++ * at power-up. ++ * Corrupted registers: r0-r7, r9-r11 ++ * ++ * Based on cache-v7.S: v7_flush_dcache_all() ++ */ ++ ++ENTRY(v7_all_dcache_invalidate) ++ mrc p15, 1, r0, c0, c0, 1 @ read clidr ++ ands r3, r0, #0x7000000 @ extract loc from clidr ++ mov r3, r3, lsr #23 @ left align loc bit field ++ beq finished @ if loc is 0, then no need to clean ++ mov r10, #0 @ start clean at cache level 0 ++loop1: ++ add r2, r10, r10, lsr #1 @ work out 3x current cache level ++ mov r1, r0, lsr r2 @ extract cache type bits from clidr ++ and r1, r1, #7 @ mask of bits for current cache only ++ cmp r1, #2 @ see what cache we have at this level ++ blt skip @ skip if no cache, or just i-cache ++ mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr ++ isb @ isb to sych the new cssr&csidr ++ mrc p15, 1, r1, c0, c0, 0 @ read the new csidr ++ and r2, r1, #7 @ extract the length of the cache lines ++ add r2, r2, #4 @ add 4 (line length offset) ++ ldr r4, =0x3ff ++ ands r4, r4, r1, lsr #3 @ find maximum number on the way size ++ clz r5, r4 @ find bit pos of way size increment ++ ldr r7, =0x7fff ++ ands r7, r7, r1, lsr #13 @ extract max number of the index size ++loop2: ++ mov r9, r4 @ create working copy of max way size ++loop3: ++ orr r11, r10, r9, lsl r5 @ factor way and cache number into r11 ++ orr r11, r11, r7, lsl r2 @ factor index number into r11 ++ mcr p15, 0, r11, c7, c6, 2 @ Invalidate line ++ subs r9, r9, #1 @ decrement the way ++ bge loop3 ++ subs r7, r7, #1 @ decrement the index ++ bge loop2 ++skip: ++ add r10, r10, #2 @ increment cache number ++ cmp r3, r10 ++ bgt loop1 ++finished: ++ mov r10, #0 @ swith back to cache level 0 ++ mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr ++ dsb ++ isb ++ mov pc, lr ++ENDPROC(v7_all_dcache_invalidate) |