exynos: Set up caching in the bootblock.

This improves firmware boot time substantially. Because cbmem isn't available
yet, we need to allocate some space in sram for the ttb. Doing cache
initialization in the bootblock means we can implement this once per CPU
instead of once per mainboard.

Old-Change-Id: Iad339de24df8ec2e23f91fe7bf57744e4cc766c5
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/65938
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit c32b9b32ad933e627b9ea98434b392239b1fea73)

exynos5420: flush caches and disable MMU in resume path

This patch flushes the caches and disables the MMU before resuming.

c32b9b3 ("Set up caching in the bootblock.") had a bug where the
dcache and MMU remained enabled in the resume path. This caused
the machine to hang on resume. However, other bugs were preventing
us from testing this properly earlier on so it went unnoticed until
now.

Signed-off-by: David Hendricks <dhendrix@chromium.org>

Old-Change-Id: Ib1774f09d286a4d659da9fc2dad1d7a6fc1ebe5e
Reviewed-on: https://chromium-review.googlesource.com/67007
Reviewed-by: ron minnich <rminnich@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 4fdf9763d25f70fd1e3591f6ff9785f78dd6170d)

Squashed two related commits.

Change-Id: Ibd42b28bb06930159248130e5ceaddb3b4b6cc2a
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6511
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>

7 files changed, 47 insertions, 29 deletions

diff --git a/src/arch/armv7/Makefile.inc b/src/arch/armv7/Makefile.inc
index 2188706e06..bf2f332f4f 100644
--- a/src/arch/armv7/Makefile.inc
+++ b/src/arch/armv7/Makefile.inc
@@ -56,6 +56,7 @@ bootblock-y += eabi_compat.c
 bootblock-y += memset.S
 bootblock-y += memcpy.S
 bootblock-y += memmove.S
+bootblock-y += mmu.c
 
 bootblock_lds = $(src)/arch/armv7/bootblock.lds
 bootblock_lds += $(chipset_bootblock_lds)
diff --git a/src/arch/armv7/mmu.c b/src/arch/armv7/mmu.c
index 7d6d46a8a1..17ad8b73ed 100644
--- a/src/arch/armv7/mmu.c
+++ b/src/arch/armv7/mmu.c
@@ -27,6 +27,7 @@
  * SUCH DAMAGE.
  */
 
+#include <config.h>
 #include <stdlib.h>
 #include <stdint.h>
 
@@ -36,14 +37,12 @@
 #include <arch/cache.h>
 #include <arch/io.h>
 
-#define L1_TLB_ENTRIES	4096	/* 1 entry for each 1MB address space */
-
-static uintptr_t ttb_addr;
+static void *const ttb_buff = (void *)CONFIG_TTB_BUFFER;
 
 void mmu_disable_range(unsigned long start_mb, unsigned long size_mb)
 {
 	unsigned int i;
-	uint32_t *ttb_entry = (uint32_t *)ttb_addr;
+	uint32_t *ttb_entry = ttb_buff;
 	printk(BIOS_DEBUG, "Disabling: 0x%08lx:0x%08lx\n",
 			start_mb*MiB, start_mb*MiB + size_mb*MiB - 1);
 
@@ -61,7 +60,7 @@ void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
 {
 	unsigned int i;
 	uint32_t attr;
-	uint32_t *ttb_entry = (uint32_t *)ttb_addr;
+	uint32_t *ttb_entry = ttb_buff;
 	const char *str = NULL;
 
 	/*
@@ -116,24 +115,14 @@ void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
 
 void mmu_init(void)
 {
-	unsigned int ttb_size;
-	uint32_t ttbcr;
-
 	/*
 	 * For coreboot's purposes, we will create a simple L1 page table
 	 * in RAM with 1MB section translation entries over the 4GB address
 	 * space.
 	 * (ref: section 10.2 and example 15-4 in Cortex-A series
 	 * programmer's guide)
-	 *
-	 * FIXME: TLB needs to be aligned to 16KB, but cbmem_add() aligns to
-	 * 512 bytes. So allocate some extra space in cbmem and fix-up the
-	 * pointer.
-	 */
-	ttb_size = L1_TLB_ENTRIES * sizeof(uint32_t);
-	ttb_addr = (uintptr_t)cbmem_add(CBMEM_ID_GDT, ttb_size + 16*KiB);
-	ttb_addr = ALIGN(ttb_addr, 16*KiB);
-	printk(BIOS_DEBUG, "Translation table is @ 0x%08x\n", ttb_addr);
+         */
+	printk(BIOS_DEBUG, "Translation table is @ %p\n", ttb_buff);
 
 	/*
 	 * Disable TTBR1 by setting TTBCR.N to 0b000, which means the TTBR0
@@ -141,16 +130,14 @@ void mmu_init(void)
 	 *
 	 * ref: Arch Ref. Manual for ARMv7-A, B3.5.4,
 	 */
-	ttbcr = read_ttbcr();
-	ttbcr &= ~(0x3);
-	write_ttbcr(ttbcr);
+	write_ttbcr(read_ttbcr() & ~0x3);
 
 	/*
 	 * Translation table base 0 address is in bits 31:14-N, where N is given
 	 * by bits 2:0 in TTBCR (which we set to 0). All lower bits in this
 	 * register should be zero for coreboot.
 	 */
-	write_ttbr0(ttb_addr);
+	write_ttbr0((uintptr_t)ttb_buff);
 
 	/* disable domain-level checking of permissions */
 	write_dacr(~0);
diff --git a/src/cpu/samsung/exynos5250/Kconfig b/src/cpu/samsung/exynos5250/Kconfig
index e0e179dd64..f937e7b21e 100644
--- a/src/cpu/samsung/exynos5250/Kconfig
+++ b/src/cpu/samsung/exynos5250/Kconfig
@@ -85,6 +85,15 @@ config CBFS_CACHE_SIZE
 	hex "size of CBFS cache data"
 	default 0x00018000
 
+# TTB needs to be aligned to 16KB.
+config TTB_BUFFER
+	hex "memory address of the TTB buffer"
+	default 0x02058000
+
+config TTB_SIZE
+	hex "size of the TTB buffer"
+	default 0x4000
+
 config SYS_SDRAM_BASE
 	hex
 	default 0x40000000
diff --git a/src/cpu/samsung/exynos5420/Kconfig b/src/cpu/samsung/exynos5420/Kconfig
index 66679a000b..fe475ab4b3 100644
--- a/src/cpu/samsung/exynos5420/Kconfig
+++ b/src/cpu/samsung/exynos5420/Kconfig
@@ -46,6 +46,7 @@ config CBFS_ROM_OFFSET
 # 0x0202_4400: variable length bootblock checksum header.
 # 0x0202_4410: bootblock, assume up to 32KB in size
 # 0x0203_0000: romstage, assume up to 128KB in size.
+# 0x0205_8000: TTB buffer.
 # 0x0205_c000: cache for CBFS data.
 # 0x0206_f000: stack bottom
 # 0x0207_3000: stack pointer
@@ -110,6 +111,14 @@ config CBFS_CACHE_SIZE
 	hex "size of CBFS cache data"
 	default 0x00013000
 
+config TTB_BUFFER
+	hex "memory address of the TTB buffer"
+	default 0x02058000
+
+config TTB_SIZE
+	hex "size of the TTB buffer"
+	default 0x4000
+
 config SYS_SDRAM_BASE
 	hex
 	default 0x20000000
diff --git a/src/cpu/samsung/exynos5420/bootblock.c b/src/cpu/samsung/exynos5420/bootblock.c
index 5cc9ef6af2..3df51a7421 100644
--- a/src/cpu/samsung/exynos5420/bootblock.c
+++ b/src/cpu/samsung/exynos5420/bootblock.c
@@ -17,10 +17,17 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <arch/cache.h>
+
 #include "clk.h"
 #include "wakeup.h"
 #include "cpu.h"
 
+/* convenient shorthand (in MB) */
+#define SRAM_START	(0x02020000 >> 20)
+#define SRAM_SIZE	1
+#define SRAM_END	(SRAM_START + SRAM_SIZE)	/* plus one... */
+
 void bootblock_cpu_init(void);
 void bootblock_cpu_init(void)
 {
@@ -51,6 +58,14 @@ void bootblock_cpu_init(void)
 		/* Never returns. */
 	}
 
+	/* set up dcache and MMU */
+	mmu_init();
+	mmu_config_range(0, SRAM_START, DCACHE_OFF);
+	mmu_config_range(SRAM_START, SRAM_SIZE, DCACHE_WRITEBACK);
+	mmu_config_range(SRAM_END, 4096 - SRAM_END, DCACHE_OFF);
+	dcache_invalidate_all();
+	dcache_mmu_enable();
+
 	/* For most ARM systems, we have to initialize firmware media source
 	 * (ex, SPI, SD/MMC, or eMMC) now; but for Exynos platform, that is
 	 * already handled by iROM so there's no need to setup again.
diff --git a/src/cpu/samsung/exynos5420/wakeup.c b/src/cpu/samsung/exynos5420/wakeup.c
index 5764c83bd6..af7ef73f89 100644
--- a/src/cpu/samsung/exynos5420/wakeup.c
+++ b/src/cpu/samsung/exynos5420/wakeup.c
@@ -17,6 +17,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <arch/cache.h>
 #include <console/console.h>
 #include "power.h"
 #include "wakeup.h"
@@ -27,6 +28,8 @@ void wakeup(void)
 		power_reset();
 
 	power_init();  /* Ensure ps_hold_setup() for early wakeup. */
+	dcache_mmu_disable();
+	icache_invalidate_all();
 	power_exit_wakeup();
 	/* Should never return. */
 	die("Failed to wake up.\n");
diff --git a/src/mainboard/google/pit/mainboard.c b/src/mainboard/google/pit/mainboard.c
index e453e679e4..a02967b1c6 100644
--- a/src/mainboard/google/pit/mainboard.c
+++ b/src/mainboard/google/pit/mainboard.c
@@ -43,7 +43,6 @@
 /* convenient shorthand (in MB) */
 #define DRAM_START	(CONFIG_SYS_SDRAM_BASE >> 20)
 #define DRAM_SIZE	CONFIG_DRAM_SIZE_MB
-#define DRAM_END	(DRAM_START + DRAM_SIZE)	/* plus one... */
 
 static struct edid edid = {
 	.ha = 1366,
@@ -432,14 +431,9 @@ static void mainboard_enable(device_t dev)
 {
 	dev->ops->init = &mainboard_init;
 
-	/* set up dcache and MMU */
-	/* FIXME: this should happen via resource allocator */
-	mmu_init();
-	mmu_config_range(0, DRAM_START, DCACHE_OFF);
+	/* set up caching for the DRAM */
 	mmu_config_range(DRAM_START, DRAM_SIZE, DCACHE_WRITEBACK);
-	mmu_config_range(DRAM_END, 4096 - DRAM_END, DCACHE_OFF);
-	dcache_invalidate_all();
-	dcache_mmu_enable();
+	tlb_invalidate_all();
 
 	/* this is going to move, but we must have it now and we're
 	 * not sure where */