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authorStefan Reinauer <reinauer@chromium.org>2013-05-24 14:38:48 -0700
committerStefan Reinauer <stefan.reinauer@coreboot.org>2013-07-10 21:43:38 +0200
commit93ce3b3a28dc0aad0bb501072bc7fc31e9cd6ce2 (patch)
tree0cf9783cc99642c3c62d23cdfdf5d5c2066b8d4d /src/arch/armv7/mmu.c
parent5420e0913144e3abbd0f36dbfbc0bcbe8f052e7b (diff)
downloadcoreboot-93ce3b3a28dc0aad0bb501072bc7fc31e9cd6ce2.tar.xz
ARMv7: flatten arch/armv7 source tree
With only 19 source files it doesn't make a whole lot of sense to create sub directories in arch/armv7, especially since the files were distributed somewhat randomly. Change-Id: I029c7848e915edf1737e1c401c034837c95d179d Signed-off-by: Stefan Reinauer <reinauer@chromium.org> Signed-off-by: Gabe Black <gabeblack@chromium.org> Reviewed-on: http://review.coreboot.org/3659 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/arch/armv7/mmu.c')
-rw-r--r--src/arch/armv7/mmu.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/src/arch/armv7/mmu.c b/src/arch/armv7/mmu.c
new file mode 100644
index 0000000000..7d6d46a8a1
--- /dev/null
+++ b/src/arch/armv7/mmu.c
@@ -0,0 +1,157 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2013 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+
+#include <cbmem.h>
+#include <console/console.h>
+
+#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;
+
+void mmu_disable_range(unsigned long start_mb, unsigned long size_mb)
+{
+ unsigned int i;
+ uint32_t *ttb_entry = (uint32_t *)ttb_addr;
+ printk(BIOS_DEBUG, "Disabling: 0x%08lx:0x%08lx\n",
+ start_mb*MiB, start_mb*MiB + size_mb*MiB - 1);
+
+ for (i = start_mb; i < start_mb + size_mb; i++)
+ writel(0, &ttb_entry[i]);
+
+ for (i = start_mb; i < start_mb + size_mb; i++) {
+ dccmvac((uintptr_t)&ttb_entry[i]);
+ tlbimvaa(i*MiB);
+ }
+}
+
+void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
+ enum dcache_policy policy)
+{
+ unsigned int i;
+ uint32_t attr;
+ uint32_t *ttb_entry = (uint32_t *)ttb_addr;
+ const char *str = NULL;
+
+ /*
+ * Section entry bits:
+ * 31:20 - section base address
+ * 18 - 0 to indicate normal section (versus supersection)
+ * 17 - nG, 0 to indicate page is global
+ * 16 - S, 0 for non-shareable (?)
+ * 15 - APX, 0 for full access
+ * 14:12 - TEX, 0b000 for outer and inner write-back
+ * 11:10 - AP, 0b11 for full access
+ * 9 - P, ? (FIXME: not described or possibly obsolete?)
+ * 8: 5 - Domain
+ * 4 - XN, 1 to set execute-never (and also avoid prefetches)
+ * 3 - C, 1 for cacheable
+ * 2 - B, 1 for bufferable
+ * 1: 0 - 0b10 to indicate section entry
+ */
+
+ switch(policy) {
+ case DCACHE_OFF:
+ /* XN set to avoid prefetches to uncached/unbuffered regions */
+ attr = (0x3 << 10) | (1 << 4) | 0x2;
+ str = "off";
+ break;
+ case DCACHE_WRITEBACK:
+ attr = (0x3 << 10) | (1 << 3) | (1 << 2) | 0x2;
+ str = "writeback";
+ break;
+ case DCACHE_WRITETHROUGH:
+ attr = (0x3 << 10) | (1 << 3) | (1 << 2) | 0x2;
+ str = "writethrough";
+ break;
+ default:
+ printk(BIOS_ERR, "unknown dcache policy: %02x\n", policy);
+ return;
+ }
+
+ printk(BIOS_DEBUG, "Setting dcache policy: 0x%08lx:0x%08lx [%s]\n",
+ start_mb << 20, ((start_mb + size_mb) << 20) - 1, str);
+
+ /* Write out page table entries. */
+ for (i = start_mb; i < start_mb + size_mb; i++)
+ writel((i << 20) | attr, &ttb_entry[i]);
+
+ /* Flush the page table entries, and old translations from the TLB. */
+ for (i = start_mb; i < start_mb + size_mb; i++) {
+ dccmvac((uintptr_t)&ttb_entry[i]);
+ tlbimvaa(i*MiB);
+ }
+}
+
+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);
+
+ /*
+ * Disable TTBR1 by setting TTBCR.N to 0b000, which means the TTBR0
+ * table size is 16KB and has indices VA[31:20].
+ *
+ * ref: Arch Ref. Manual for ARMv7-A, B3.5.4,
+ */
+ ttbcr = read_ttbcr();
+ ttbcr &= ~(0x3);
+ write_ttbcr(ttbcr);
+
+ /*
+ * 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);
+
+ /* disable domain-level checking of permissions */
+ write_dacr(~0);
+}