Add submodule dependency filesHEADmaster

Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec

1 files changed, 242 insertions, 0 deletions

diff --git a/roms/skiboot/external/common/arch_flash_powerpc.c b/roms/skiboot/external/common/arch_flash_powerpc.c
new file mode 100644
index 000000000..87661296d
--- /dev/null
+++ b/roms/skiboot/external/common/arch_flash_powerpc.c
@@ -0,0 +1,242 @@
+// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+/* Copyright 2013-2017 IBM Corp.
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <stdbool.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include <libflash/file.h>
+
+#include "arch_flash.h"
+
+#define FDT_FLASH_PATH "/proc/device-tree/chosen/ibm,system-flash"
+#define SYSFS_MTD_PATH "/sys/class/mtd"
+
+static inline void hint_root(void)
+{
+	fprintf(stderr, "Do you have permission? Are you root?\n");
+}
+
+static int get_dev_attr(const char *dev, const char *attr_file, uint32_t *attr)
+{
+	char *dev_path = NULL;
+	int fd, rc;
+
+	/*
+	 * Needs to be large enough to hold at most uint32_t represented as a
+	 * string in hex with leading 0x
+	 */
+	char attr_buf[10];
+
+	rc = asprintf(&dev_path, "%s/%s/%s", SYSFS_MTD_PATH, dev, attr_file);
+	if (rc < 0) {
+		dev_path = NULL;
+		goto out;
+	}
+
+	fd = open(dev_path, O_RDONLY);
+	if (fd == -1)
+		goto out;
+
+	rc = read(fd, attr_buf, sizeof(attr_buf));
+	close(fd);
+	if (rc == -1)
+		goto out;
+
+	if (attr)
+		*attr = strtol(attr_buf, NULL, 0);
+
+	free(dev_path);
+	return 0;
+
+out:
+	free(dev_path);
+	fprintf(stderr, "Couldn't get MTD attribute '%s' from '%s'\n", dev, attr_file);
+	return -1;
+}
+
+static int get_dev_mtd(const char *fdt_flash_path, char **mtd_path)
+{
+	struct dirent **namelist;
+	char fdt_node_path[PATH_MAX];
+	int count, i, rc, fd;
+	bool done;
+
+	if (!fdt_flash_path)
+		return -1;
+
+	fd = open(fdt_flash_path, O_RDONLY);
+	if (fd == -1) {
+		fprintf(stderr, "Couldn't open '%s' FDT attribute to determine which flash device to use\n",
+				fdt_flash_path);
+		fprintf(stderr, "Is your skiboot new enough to expose the flash through the device tree?\n");
+		hint_root();
+		return -1;
+	}
+
+	rc = read(fd, fdt_node_path, sizeof(fdt_node_path));
+	close(fd);
+	if (rc == -1) {
+		fprintf(stderr, "Couldn't read flash FDT node from '%s'\n", fdt_flash_path);
+		hint_root();
+		return -1;
+	}
+
+	count = scandir(SYSFS_MTD_PATH, &namelist, NULL, alphasort);
+	if (count == -1) {
+		fprintf(stderr, "Couldn't scan '%s' for MTD\n", SYSFS_MTD_PATH);
+		hint_root();
+		return -1;
+	}
+
+	rc = 0;
+	done = false;
+	for (i = 0; i < count; i++) {
+		struct dirent *dirent;
+		char *dev_path;
+		char fdt_node_path_tmp[PATH_MAX];
+
+		dirent = namelist[i];
+
+		/*
+		 * The call to asprintf must happen last as when it succeeds it
+		 * will allocate dev_path
+		 */
+		if (dirent->d_name[0] == '.' || rc || done ||
+			asprintf(&dev_path, "%s/%s/device/of_node", SYSFS_MTD_PATH, dirent->d_name) < 0) {
+			free(namelist[i]);
+			continue;
+		}
+
+		rc = readlink(dev_path, fdt_node_path_tmp, sizeof(fdt_node_path_tmp) - 1);
+		free(dev_path);
+		if (rc == -1) {
+			/*
+			 * This might fail because it could not exist if the system has flash
+			 * devices that present as mtd but don't have corresponding FDT
+			 * nodes, just continue silently.
+			 */
+			free(namelist[i]);
+			/* Should still try the next dir so reset rc */
+			rc = 0;
+			continue;
+		}
+		fdt_node_path_tmp[rc] = '\0';
+
+		if (strstr(fdt_node_path_tmp, fdt_node_path)) {
+			uint32_t flags, size;
+
+			/*
+			 * size and flags could perhaps have be gotten another way but this
+			 * method is super unlikely to fail so it will do.
+			 */
+
+			/* Check to see if device is writeable */
+			rc = get_dev_attr(dirent->d_name, "flags", &flags);
+			if (rc) {
+				free(namelist[i]);
+				continue;
+			}
+
+			/* Get the size of the mtd device while we're at it */
+			rc = get_dev_attr(dirent->d_name, "size", &size);
+			if (rc) {
+				free(namelist[i]);
+				continue;
+			}
+
+			rc = asprintf(&dev_path, "/dev/%s", dirent->d_name);
+			if (rc < 0) {
+				free(namelist[i]);
+				continue;
+			}
+			rc = 0;
+			*mtd_path = dev_path;
+			done = true;
+		}
+		free(namelist[i]);
+	}
+	free(namelist);
+
+	if (!done) {
+		fprintf(stderr, "Couldn't find '%s' corresponding MTD\n", fdt_flash_path);
+		fprintf(stderr, "Is your kernel new enough to expose MTD?\n");
+	}
+
+	/* explicit negative value so as to not return a libflash code */
+	return done ? rc : -1;
+}
+
+static struct blocklevel_device *arch_init_blocklevel(const char *file, bool keep_alive)
+{
+	int rc;
+	struct blocklevel_device *new_bl = NULL;
+	char *real_file = NULL;
+
+	if (!file) {
+		rc = get_dev_mtd(FDT_FLASH_PATH, &real_file);
+		if (rc)
+			return NULL;
+	}
+
+	rc = file_init_path(file ? file : real_file, NULL, keep_alive, &new_bl);
+	if (rc)
+		new_bl = NULL;
+	free(real_file);
+	return new_bl;
+}
+
+/* Skiboot will worry about this for us */
+int __attribute__((const)) arch_flash_set_wrprotect(struct blocklevel_device *bl, int set)
+{
+	(void)bl;
+	(void)set;
+
+	return 0;
+}
+
+enum flash_access __attribute__((const)) arch_flash_access(struct blocklevel_device *bl,
+		enum flash_access access)
+{
+	(void)bl;
+
+	if (access != PNOR_MTD)
+		return ACCESS_INVAL;
+
+	return PNOR_MTD;
+}
+
+int arch_flash_init(struct blocklevel_device **r_bl, const char *file, bool keep_alive)
+{
+	struct blocklevel_device *new_bl;
+
+	/*
+	 * In theory here we should check that something crazy wasn't
+	 * passed to arch_flash_access() and refuse to init.
+	 * However, arch_flash_access won't accept anything except
+	 * PNOR_MTD, if they want something different then they should
+	 * have checked with arch_flash_access()
+	 */
+	new_bl = arch_init_blocklevel(file, keep_alive);
+	if (!new_bl)
+		return -1;
+
+	*r_bl = new_bl;
+	return 0;
+}
+
+void arch_flash_close(struct blocklevel_device *bl, const char *file)
+{
+	(void)file;
+
+	file_exit_close(bl);
+}