Merge pull request #1193 from jwerner-chromium/JW_coreboot

New console API and coreboot support [v4]

2 files changed, 147 insertions, 0 deletions

diff --git a/lib/coreboot/coreboot.mk b/lib/coreboot/coreboot.mk
new file mode 100644
index 00000000..bbaa3329
--- /dev/null
+++ b/lib/coreboot/coreboot.mk
@@ -0,0 +1,24 @@
+#
+# Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+COREBOOT := 0
+$(eval $(call assert_boolean,COREBOOT))
+$(eval $(call add_define,COREBOOT))
+
+ifeq (${COREBOOT},1)
+
+ifneq (${ARCH},aarch64)
+$(error "coreboot only supports Trusted Firmware on AArch64.")
+endif
+
+BL31_SOURCES	+=	$(addprefix lib/coreboot/,	\
+			coreboot_table.c)
+
+BL31_SOURCES	+=	drivers/coreboot/cbmem_console/${ARCH}/cbmem_console.S
+
+INCLUDES	+=	-Iinclude/drivers/coreboot
+
+endif	# COREBOOT
diff --git a/lib/coreboot/coreboot_table.c b/lib/coreboot/coreboot_table.c
new file mode 100644
index 00000000..64f8879e
--- /dev/null
+++ b/lib/coreboot/coreboot_table.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <cbmem_console.h>
+#include <coreboot.h>
+#include <debug.h>
+#include <mmio.h>
+#include <string.h>
+#include <xlat_tables_v2.h>
+
+/*
+ * Structures describing coreboot's in-memory descriptor tables. See
+ * <coreboot>/src/commonlib/include/commonlib/coreboot_tables.h for
+ * canonical implementation.
+ */
+
+typedef struct {
+	char signature[4];
+	uint32_t header_bytes;
+	uint32_t header_checksum;
+	uint32_t table_bytes;
+	uint32_t table_checksum;
+	uint32_t table_entries;
+} cb_header_t;
+
+typedef enum {
+	CB_TAG_SERIAL = 0xf,
+	CB_TAG_CBMEM_CONSOLE = 0x17,
+} cb_tag_t;
+
+typedef struct {
+	uint32_t tag;
+	uint32_t size;
+	union {
+		coreboot_serial_t serial;
+		uint64_t uint64;
+	};
+} cb_entry_t;
+
+coreboot_serial_t coreboot_serial;
+
+/*
+ * The coreboot table is parsed before the MMU is enabled (i.e. with strongly
+ * ordered memory), so we cannot make unaligned accesses. The table entries
+ * immediately follow one another without padding, so nothing after the header
+ * is guaranteed to be naturally aligned. Therefore, we need to define safety
+ * functions that can read unaligned integers.
+ */
+static uint32_t read_le32(uint32_t *p)
+{
+	uintptr_t addr = (uintptr_t)p;
+	return mmio_read_8(addr)		|
+	       mmio_read_8(addr + 1) << 8	|
+	       mmio_read_8(addr + 2) << 16	|
+	       mmio_read_8(addr + 3) << 24;
+}
+static uint64_t read_le64(uint64_t *p)
+{
+	return read_le32((void *)p) | (uint64_t)read_le32((void *)p + 4) << 32;
+}
+
+static void expand_and_mmap(uintptr_t baseaddr, size_t size)
+{
+	uintptr_t pageaddr = round_down(baseaddr, PAGE_SIZE);
+	size_t expanded = round_up(baseaddr - pageaddr + size, PAGE_SIZE);
+	mmap_add_region(pageaddr, pageaddr, expanded,
+			MT_MEMORY | MT_RW | MT_NS | MT_EXECUTE_NEVER);
+}
+
+static void setup_cbmem_console(uintptr_t baseaddr)
+{
+	static console_cbmc_t console;
+	assert(!console.base);		/* should only have one CBMEM console */
+
+	/* CBMEM console structure stores its size in first header field. */
+	uint32_t size = *(uint32_t *)baseaddr;
+	expand_and_mmap(baseaddr, size);
+	console_cbmc_register(baseaddr, &console);
+	console_set_scope(&console.console, CONSOLE_FLAG_BOOT |
+					    CONSOLE_FLAG_RUNTIME |
+					    CONSOLE_FLAG_CRASH);
+}
+
+void coreboot_table_setup(void *base)
+{
+	cb_header_t *header = base;
+	void *ptr;
+	int i;
+
+	if (strncmp(header->signature, "LBIO", 4)) {
+		ERROR("coreboot table signature corrupt!\n");
+		return;
+	}
+
+	ptr = base + header->header_bytes;
+	for (i = 0; i < header->table_entries; i++) {
+		cb_entry_t *entry = ptr;
+
+		if (ptr - base >= header->header_bytes + header->table_bytes) {
+			ERROR("coreboot table exceeds its bounds!\n");
+			break;
+		}
+
+		switch (read_le32(&entry->tag)) {
+		case CB_TAG_SERIAL:
+			memcpy(&coreboot_serial, &entry->serial,
+			       sizeof(coreboot_serial));
+			break;
+		case CB_TAG_CBMEM_CONSOLE:
+			setup_cbmem_console(read_le64(&entry->uint64));
+			break;
+		default:
+			/* There are many tags TF doesn't need to care about. */
+			break;
+		}
+
+		ptr += read_le32(&entry->size);
+	}
+}