core/pldm: Lid ids string parsing

This patch parses the "hb_lid_ids" string from bios tables and complete
the global list of lid files. Each entry in the list contains the name,
the id, the length of the lid file and the virtual address start access.
This virtual address is used for for PNOR Resource Provider operations.
16 MB of VMM address are reserved  space per section.

Signed-off-by: Christophe Lombard <clombard@linux.ibm.com>
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>

3 files changed, 194 insertions, 1 deletions

diff --git a/core/pldm/Makefile.inc b/core/pldm/Makefile.inc
index d89e4c2..87952db 100644
--- a/core/pldm/Makefile.inc
+++ b/core/pldm/Makefile.inc
@@ -10,7 +10,7 @@ CPPFLAGS += -I$(SRC)/pldm/include/libpldm/oem/ibm/
 PLDM_OBJS = pldm-mctp.o pldm-responder.o pldm-requester.o
 PLDM_OBJS += pldm-base-requests.o pldm-platform-requests.o
 PLDM_OBJS += pldm-bios-requests.o pldm-fru-requests.o
-PLDM_OBJS += pldm-file-io-requests.o
+PLDM_OBJS += pldm-file-io-requests.o pldm-lid-files.o
 
 PLDM = $(PLDM_DIR)/built-in.a
 $(PLDM): $(PLDM_OBJS:%=$(PLDM_DIR)/%)
diff --git a/core/pldm/pldm-lid-files.c b/core/pldm/pldm-lid-files.c
new file mode 100644
index 0000000..a46a731
--- /dev/null
+++ b/core/pldm/pldm-lid-files.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+// Copyright 2022 IBM Corp.
+
+#define pr_fmt(fmt) "PLDM: " fmt
+
+#include <endian.h>
+#include <lock.h>
+#include <opal-api.h>
+#include <libflash/errors.h>
+#include <libflash/ffs.h>
+#include "pldm.h"
+
+/*
+ * This struct is used to map a PNOR sections.
+ * The content is deriving from the hb_lid_ids PLDM BIOS Attribute.
+ */
+struct pldm_lid {
+	struct list_node	list;
+	uint32_t		start;
+	uint32_t		handle;
+	uint32_t		length;
+	char			name[FFS_PART_NAME_MAX + 1];
+	char			id[FFS_PART_NAME_MAX + 1];
+};
+
+static LIST_HEAD(lid_files);
+
+#define MEGABYTE (1024*1024)
+
+/*
+ * When using PLDM for PNOR Resource Provider operations,
+ * reserve 32 MB of VMM address space per section.
+ * Note that all of this space may not actually be used by each section.
+ */
+#define VMM_SIZE_RESERVED_PER_SECTION (32 * MEGABYTE)
+
+/*
+ * Print the attributes of lid files.
+ */
+static void print_lid_files_attr(void)
+{
+	struct pldm_lid *lid = NULL;
+
+	list_for_each(&lid_files, lid, list)
+		prlog(PR_NOTICE, "name: %s, id: %s, handle: %d, length: 0x%x, start: 0x%x\n",
+				 lid->name, lid->id, lid->handle, lid->length, lid->start);
+}
+
+/*
+ * Return the number of lid files.
+ */
+static uint32_t get_lids_count(void)
+{
+	struct pldm_lid *lid = NULL;
+	uint32_t count = 0;
+
+	list_for_each(&lid_files, lid, list)
+		count++;
+
+	return count;
+}
+
+/*
+ * parse the "hb_lid_ids" string
+ * <ATTR_a>=<lid_id_1>,<ATTR_b>=<lid_id_2>
+ */
+static int parse_hb_lid_ids_string(char *str)
+{
+	struct pldm_lid *lid, *tmp;
+	const char *pp = "=";
+	char *attr, *attr_end;
+	int rc, count = 1;
+	char *lid_id;
+
+	for (char *p = strtok(str, ","); p != NULL; p = strtok(NULL, ",")) {
+		lid = zalloc(sizeof(struct pldm_lid));
+		if (!lid) {
+			prlog(PR_ERR, "Error allocating pldm_lid structure\n");
+			rc = OPAL_NO_MEM;
+			goto err;
+		}
+
+		/* parse the string <attr>=<lid_id> */
+		attr = p;
+		while ((*pp != *p) && (*p != '\0'))
+			p++;
+
+		attr_end = p;
+		lid_id = ++p;
+		*attr_end = '\0';
+
+		strcpy(lid->name, attr);
+		strcpy(lid->id, lid_id);
+
+		/* reserve 32 MB of VMM address space per section.
+		 * Address 0x0 -> 0x2000000:   'fake' header flash
+		 * Address 0x2000000 -> 0x4000000: lid id 1
+		 * Address 0x4000000 -> 0x6000000: lid id 2
+		 * ....
+		 */
+		lid->start = VMM_SIZE_RESERVED_PER_SECTION * count;
+
+		/* handle and length */
+		rc = pldm_find_file_handle_by_lid_id(lid->id,
+						     &lid->handle,
+						     &lid->length);
+		/* OPAL_PARAMETER means that lid_id is present in hb_lid_ids,
+		 * but we don't have any file attribute information in the
+		 * file table, so continue on the next item.
+		 */
+		if ((rc) && (rc != OPAL_PARAMETER))
+			goto err;
+
+		if (lid->length > VMM_SIZE_RESERVED_PER_SECTION) {
+			prlog(PR_ERR, "file length (0x%x) > virtual size reserved per "
+				      "section (0x%x)\n",
+				      lid->length, VMM_SIZE_RESERVED_PER_SECTION);
+			rc = OPAL_RESOURCE;
+			goto err;
+		}
+
+		/* add new member in the global list */
+		list_add_tail(&lid_files, &lid->list);
+
+		count++;
+	}
+
+	return OPAL_SUCCESS;
+
+err:
+	/* free all lid entries */
+	list_for_each_safe(&lid_files, lid, tmp, list)
+		free(lid);
+
+	return rc;
+}
+
+/*
+ * Parse the "hb_lid_ids" string from bios tables and complete
+ * the global list of lid files.
+ */
+static int lid_ids_to_vaddr_mapping(void)
+{
+	char *lid_ids_string = NULL;
+	int rc;
+
+	/* get lid ids string from bios tables */
+	rc = pldm_bios_get_lids_id(&lid_ids_string);
+	if (rc)
+		goto out;
+
+	/* parse the "hb_lid_ids" string */
+	rc = parse_hb_lid_ids_string(lid_ids_string);
+
+out:
+	if (lid_ids_string)
+		free(lid_ids_string);
+
+	return rc;
+}
+
+int pldm_lid_files_init(struct blocklevel_device **bl)
+{
+	uint32_t lid_files_count;
+	int rc;
+
+	if (!bl)
+		return FLASH_ERR_PARM_ERROR;
+
+	*bl = NULL;
+
+	/* convert lid ids data to pnor structure */
+	rc = lid_ids_to_vaddr_mapping();
+	if (rc)
+		goto err;
+
+	lid_files_count = get_lids_count();
+
+	prlog(PR_NOTICE, "Number of lid files: %d\n", lid_files_count);
+	print_lid_files_attr();
+
+	return OPAL_SUCCESS;
+
+err:
+	return rc;
+}
diff --git a/include/pldm.h b/include/pldm.h
index 3c23dc9..9c5369e 100644
--- a/include/pldm.h
+++ b/include/pldm.h
@@ -5,6 +5,8 @@
 #ifndef __PLDM_H__
 #define __PLDM_H__
 
+#include <skiboot.h>
+
 /**
  * Handle PLDM messages received from MCTP
  */
@@ -36,4 +38,9 @@ int pldm_platform_restart(void);
  */
 int pldm_fru_dt_add_bmc_version(void);
 
+/**
+ * Convert lid ids data to pnor structure
+ */
+int pldm_lid_files_init(struct blocklevel_device **bl);
+
 #endif /* __PLDM_H__ */