HACK: Pass data from firmware to kernel

lib/chromeos/os_storage.c

Index: lib/chromeos/os_storage.c
diff --git a/lib/chromeos/os_storage.c b/lib/chromeos/os_storage.c
index 113b732efd87363657becb4fbf1577f9dba48cd9..ddccb400d2e0a503f87e3031b2634d17ef268309 100644
--- a/lib/chromeos/os_storage.c
+++ b/lib/chromeos/os_storage.c
@@ -13,6 +13,15 @@
 #include <part.h>
 #include <chromeos/os_storage.h>
 
+/* TODO For load fmap; remove when not used */
+#include <chromeos/firmware_storage.h>
+
+/* TODO For strcpy; remove when not used */
+#include <linux/string.h>
+
+/* TODO remove when not used */
+extern uint64_t get_nvcxt_lba(void);
+
 #include <boot_device.h>
 #include <load_kernel_fw.h>
 #include <vboot_nvstorage.h>
@@ -160,6 +169,18 @@ int load_kernel_wrapper(LoadKernelParams *params,
 		void *gbb_data, uint64_t gbb_size, uint64_t boot_flags,
 		VbNvContext *nvcxt, uint8_t *shared_data_blob)
 {
+	/*
+	 * TODO(clchiou): Hack for bringing up factory; preserve recovery
+	 * reason before LoadKernel destroys it. Remove when not needed.
+	 *
+	 * XXX: I found a potential bug that for example, VbNvGet() returns
+	 *   reason == 0x81
+	 * but if you access the raw data directly, it gives you
+	 *   nvcxt->raw[RECOVERY_OFFSET] == 0x02.
+	 */
+	uint32_t reason = 0;
+	VbNvGet(&nvcxt, VBNV_RECOVERY_REQUEST, &reason);
+
 	int status = LOAD_KERNEL_NOT_FOUND;
 	block_dev_desc_t *dev_desc;
 
@@ -226,5 +247,106 @@ EXIT:
 		}
 	}
 
+	/*
+	 * TODO(clchiou): This is an urgent hack for bringing up factory. We
+	 * fill in data that will be used by kernel at last 1MB space.
+	 *
+	 * Rewrite this part after the protocol specification between
+	 * Chrome OS firmware and kernel is finalized.
+	 */
+	if (status == LOAD_KERNEL_SUCCESS) {
+		DECLARE_GLOBAL_DATA_PTR;
+
+		void *kernel_shared_data = (void*)
+			gd->bd->bi_dram[CONFIG_NR_DRAM_BANKS-1].start +
+			gd->bd->bi_dram[CONFIG_NR_DRAM_BANKS-1].size - SZ_1M;
+
+		struct {
+			uint8_t		signature[16];
+			uint32_t	chsw;
+			uint8_t		hwid[256];
+			uint8_t		fwid[256];
+			uint8_t		frid[256];
+			uint32_t	binf[5];
+			uint32_t	gpio[11];
+			uint32_t	vbnv[2];
+			uint64_t	fmap_start_address;
+			uint64_t	nvcxt_lba;
+			uint8_t		nvcxt_cache[VBNV_BLOCK_SIZE];
+		} __attribute__((packed)) *sd = kernel_shared_data;
+
+		void *kernel_shared_data_body =
+			kernel_shared_data + sizeof(*sd);
+
+		int i;
+
+		debug(PREFIX "kernel shared data at %p\n", kernel_shared_data);
+
+		memset(sd, '\0', sizeof(*sd));
+
+		strcpy((char*) sd->signature, "CHROMEOS");
+
+		/*
+		 * chsw bit value
+		 *   bit 0x00000002 : recovery button pressed
+		 *   bit 0x00000020 : developer mode enabled
+		 *   bit 0x00000200 : firmware write protect disabled
+		 */
+		if (params->boot_flags & BOOT_FLAG_RECOVERY)
+			sd->chsw |= 0x002;
+		if (params->boot_flags & BOOT_FLAG_DEVELOPER)
+			sd->chsw |= 0x020;
+		sd->chsw |= 0x200; /* so far write protect is disabled */
+
+		strcpy((char*) sd->hwid, CONFIG_CHROMEOS_HWID);
+		strcpy((char*) sd->fwid, "ARM Firmware ID");
+		strcpy((char*) sd->frid, "ARM Read-Only Firmware ID");
+
+		sd->binf[0] = 0; /* boot reason; always 0 */
+		if (params->boot_flags & BOOT_FLAG_RECOVERY) {
+			sd->binf[1] = 0; /* active main firmware */
+			sd->binf[3] = 0; /* active firmware type */
+		} else {
+			sd->binf[1] = 1; /* active main firmware */
+			sd->binf[3] = 1; /* active firmware type */
+		}
+		sd->binf[2] = 0; /* active EC firmware */
+		sd->binf[4] = reason;
+
+		/* sd->gpio[i] == 1 if it is active-high */
+		sd->gpio[1] = 1; /* only developer mode gpio is active high */
+
+		sd->vbnv[0] = 0;
+		sd->vbnv[1] = VBNV_BLOCK_SIZE;
+
+		firmware_storage_t file;
+		firmware_storage_init(&file);
+		firmware_storage_read(&file,
+				CONFIG_OFFSET_FMAP, CONFIG_LENGTH_FMAP,
+				kernel_shared_data_body);
+		file.close(file.context);
+		sd->fmap_start_address = (uint64_t) kernel_shared_data_body;
+		kernel_shared_data_body += CONFIG_LENGTH_FMAP;
+
+		sd->nvcxt_lba = get_nvcxt_lba();
+
+		memcpy(sd->nvcxt_cache,
+				params->nv_context->raw, VBNV_BLOCK_SIZE);
+
+		debug(PREFIX "chsw     %08x\n", sd->chsw);
+		for (i = 0; i < 5; i++)
+			debug(PREFIX "binf[%2d] %08x\n", i, sd->binf[i]);
+		for (i = 0; i < 11; i++)
+			debug(PREFIX "gpio[%2d] %08x\n", i, sd->gpio[i]);
+		debug(PREFIX "vbnv[ 0] %08x\n", sd->vbnv[0]);
+		debug(PREFIX "vbnv[ 1] %08x\n", sd->vbnv[1]);
+		debug(PREFIX "fmap     %08llx\n", sd->fmap_start_address);
+		debug(PREFIX "nvcxt    %08llx\n", sd->nvcxt_lba);
+		debug(PREFIX "nvcxt_c  ");
+		for (i = 0; i < VBNV_BLOCK_SIZE; i++)
+			debug("%02x", sd->nvcxt_cache[i]);
+		putc('\n');
+	}
+
 	return status;
 }