lib/flash: Add support for platform versions

Add basic libflash support to read the VERSION partition on BMC
machines. This adds a dependency on the libflash shared library from
Skiboot.
The MTD partition is accessed through the libflash helper functions.
Once read into a buffer, the VERSION partition is a simple list of
newline-terminated version strings. Some BMC platforms may have two
'sides' to flash - these are interpreted as the "current" and "other"
sides depending on which one the current Petitboot is running from.

Signed-off-by: Sam Mendoza-Jonas <sam@mendozajonas.com>

4 files changed, 273 insertions, 1 deletions

diff --git a/lib/Makefile.am b/lib/Makefile.am
index a2421a5..a3ae943 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -48,4 +48,21 @@ lib_libpbcore_la_SOURCES = \
 	lib/url/url.c \
 	lib/url/url.h \
 	lib/util/util.c \
-	lib/util/util.h
+	lib/util/util.h \
+	lib/flash/config.h \
+	lib/flash/flash.h
+
+if ENABLE_MTD
+lib_libpbcore_la_SOURCES += \
+	lib/flash/flash.c
+
+lib_libpbcore_la_CPPFLAGS += \
+	$(AM_CPPFLAGS)
+
+lib_libpbcore_la_LDFLAGS = \
+	$(AM_LDFLAGS) \
+	-l:libflash.so
+
+lib_libpbcore_la_SOURCES += \
+	lib/flash/flash.c
+endif
diff --git a/lib/flash/config.h b/lib/flash/config.h
new file mode 100644
index 0000000..a132a01
--- /dev/null
+++ b/lib/flash/config.h
@@ -0,0 +1,19 @@
+/* For CCAN */
+
+#include <endian.h>
+#include <byteswap.h>
+
+#define HAVE_TYPEOF			1
+#define HAVE_BUILTIN_TYPES_COMPATIBLE_P	1
+
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define HAVE_BIG_ENDIAN         0
+#define HAVE_LITTLE_ENDIAN      1
+#else
+#define HAVE_BIG_ENDIAN         1
+#define HAVE_LITTLE_ENDIAN      0
+#endif
+
+#define HAVE_BYTESWAP_H 1
+#define HAVE_BSWAP_64	1
diff --git a/lib/flash/flash.c b/lib/flash/flash.c
new file mode 100644
index 0000000..1056c63
--- /dev/null
+++ b/lib/flash/flash.c
@@ -0,0 +1,213 @@
+/*
+ *  Copyright (C) 2015 IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <errno.h>
+#include <asm/byteorder.h>
+
+#include <log/log.h>
+#include <talloc/talloc.h>
+#include <flash/flash.h>
+#include <ccan/endian/endian.h>
+
+#include <libflash/arch_flash.h>
+#include <libflash/blocklevel.h>
+#include <libflash/libflash.h>
+#include <libflash/libffs.h>
+#include <libflash/file.h>
+#include <libflash/ecc.h>
+
+
+struct flash_info {
+	/* Device information */
+	struct blocklevel_device	*bl;
+	struct ffs_handle		*ffs;
+	uint32_t			size;	/* raw size of partition */
+	const char			*path;
+	bool				ecc;
+	uint32_t			erase_granule;
+
+	/* Partition information */
+	uint32_t			attr_part_idx;
+	uint32_t			attr_data_pos;
+	uint32_t			attr_data_len; /* Includes ECC bytes */
+
+	/* 'Other Side' info if present */
+	struct flash_info		*other_side;
+
+};
+
+static int partition_info(struct flash_info *info, const char *partition)
+{
+	int rc;
+
+	rc = ffs_lookup_part(info->ffs, partition, &info->attr_part_idx);
+	if (rc) {
+		pb_log("Failed to find %s partition\n", partition);
+		return rc;
+	}
+
+	return ffs_part_info(info->ffs, info->attr_part_idx, NULL,
+			   &info->attr_data_pos, &info->attr_data_len,
+			   NULL, &info->ecc);
+}
+
+static struct flash_info *flash_setup_buffer(void *ctx, const char *partition)
+{
+	struct flash_info *info;
+	struct ffs_handle *tmp = NULL;
+	int rc = 0;
+
+	if (!partition)
+		return NULL;
+
+	info = talloc_zero(ctx, struct flash_info);
+	if (!info)
+		return NULL;
+
+	rc = arch_flash_init(&info->bl, NULL, true);
+	if (rc) {
+		pb_log("Failed to init mtd device\n");
+		return NULL;
+	}
+
+	rc = blocklevel_get_info(info->bl, &info->path, &info->size,
+				 &info->erase_granule);
+	if (rc) {
+		pb_log("Failed to retrieve blocklevel info\n");
+		return NULL;
+	}
+
+	rc = ffs_init(0, info->size, info->bl, &info->ffs, 1);
+	if (rc) {
+		pb_log("%s: Failed to init ffs\n", __func__);
+		goto out;
+	}
+
+	rc = partition_info(info, partition);
+	if (rc) {
+		pb_log("Failed to retrieve partition info\n");
+		goto out;
+	}
+
+	/* Check if there is a second flash side. If there is not, or
+	 * we fail to recognise it, ignore it and continue */
+	ffs_next_side(info->ffs, &tmp, info->ecc);
+	if (tmp && ffs_equal(info->ffs, tmp) == false) {
+		pb_debug("Other side present on MTD device\n");
+		info->other_side = talloc_zero(info, struct flash_info);
+		info->other_side->ffs = tmp;
+		info->other_side->bl = info->bl;
+		info->other_side->size = info->size;
+		info->other_side->path = info->path;
+		info->other_side->ecc = info->ecc;
+		info->other_side->erase_granule = info->erase_granule;
+		rc = partition_info(info->other_side, partition);
+		if (rc)
+			pb_log("Failed to retrieve partition info "
+			       "for other side - ignoring\n");
+	}
+
+	pb_debug("%s Details\n", partition);
+	pb_debug("\tName\t\t%s\n", info->path);
+	pb_debug("\tFlash Size\t%u\n", info->size);
+	pb_debug("\tGranule\t\t%u\n", info->erase_granule);
+	pb_debug("\tECC\t\t%s\n", info->ecc ? "Protected" : "Unprotected");
+	pb_debug("\tCurrent Side info:\n");
+	pb_debug("\tIndex\t\t%u\n", info->attr_part_idx);
+	pb_debug("\tOffset\t\t%u\n", info->attr_data_pos);
+	pb_debug("\tPart. Size\t%u\n", info->attr_data_len);
+	if (info->other_side) {
+		pb_debug("\tOther Side info:\n");
+		pb_debug("\tIndex\t\t%u\n", info->other_side->attr_part_idx);
+		pb_debug("\tOffset\t\t%u\n", info->other_side->attr_data_pos);
+		pb_debug("\tPart. Size\t%u\n", info->other_side->attr_data_len);
+	}
+
+	return info;
+out:
+	arch_flash_close(info->bl, NULL);
+	talloc_free(info);
+	return NULL;
+}
+
+int flash_parse_version(void *ctx, char ***versions, bool current)
+{
+	char *saveptr, *tok,  **tmp, *buffer;
+	const char *delim = "\n";
+	struct flash_info *info, *cur_info;
+	uint32_t len;
+	int rc, n = 0;
+
+	saveptr = tok = NULL;
+	tmp = NULL;
+
+	info = flash_setup_buffer(ctx, "VERSION");
+	if (!info)
+		return 0;
+
+	if (!current && !info->other_side)
+		return 0;
+
+	cur_info = current ? info->other_side : info;
+
+	len = cur_info->attr_data_len -  ecc_size(cur_info->attr_data_len);
+	buffer = talloc_array(cur_info, char, len);
+	if (!buffer) {
+		pb_log("%s: Failed to init buffer!\n", __func__);
+		goto out;
+	}
+
+	rc = blocklevel_read(cur_info->bl, cur_info->attr_data_pos,
+			     buffer, len);
+	if (rc) {
+		pb_log("Failed to read VERSION partition\n");
+		goto out;
+	}
+
+	/* open-power-platform */
+	tok = strtok_r(buffer, delim, &saveptr);
+	if (tok) {
+		tmp = talloc_realloc(ctx, tmp, char *, n + 1);
+		if (!tmp) {
+			pb_log("%s: Failed to allocate memory\n", __func__);
+			goto out;
+		}
+		tmp[n++] = talloc_strdup(ctx, tok);
+	}
+
+	tok = strtok_r(NULL, delim, &saveptr);
+	while (tok) {
+		/* Ignore leading tab from subsequent lines */
+		tmp = talloc_realloc(ctx, tmp, char *, n + 1);
+		if (!tmp) {
+			pb_log("%s: Failed to reallocate memory\n", __func__);
+			n = 0;
+			goto out;
+		}
+		tmp[n++] = talloc_strdup(ctx, tok + 1);
+		tok = strtok_r(NULL, delim, &saveptr);
+	}
+
+out:
+	pb_debug("%d version strings read from %s side\n",
+		 n, current ? "current" : "other");
+	arch_flash_close(info->bl, NULL);
+	talloc_free(info);
+	*versions = tmp;
+	return n;
+}
diff --git a/lib/flash/flash.h b/lib/flash/flash.h
new file mode 100644
index 0000000..d163d31
--- /dev/null
+++ b/lib/flash/flash.h
@@ -0,0 +1,23 @@
+/*
+ *  Copyright (C) 2015 IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ */
+
+#ifndef FLASH_H
+#define FLASH_H
+
+#include <flash/config.h>
+#include <types/types.h>
+
+int flash_parse_version(void *ctx, char ***versions, bool current);
+
+#endif /* FLASH_H */