S5L8702: Introduce syscfg_read() and use it in the debug menu

This makes it possible to reuse the SysCfg reading logic in other places.

Tested on ipod6g (normal + bootloader).

Change-Id: Iae6de2ee671bce4edb0153d26c57579ad47d0335

apps/debug_menu.c

@@ -2642,51 +2642,37 @@ static bool dbg_device_data(void)
 
 
 #if defined(IPOD_6G) && !defined(SIMULATOR)
-#define SYSCFG_MAX_ENTRIES 9 // 9 on iPod Classic/6G
-
 static bool dbg_syscfg(void) {
     struct simplelist_info info;
-    struct SysCfgHeader syscfg_hdr;
-    size_t syscfg_hdr_size = sizeof(struct SysCfgHeader);
-    size_t syscfg_entry_size = sizeof(struct SysCfgEntry);
-    struct SysCfgEntry syscfg_entries[SYSCFG_MAX_ENTRIES];
+    struct SysCfg syscfg;
 
     simplelist_info_init(&info, "SysCfg NOR contents", 0, NULL);
     simplelist_reset_lines();
 
-    bootflash_init(SPI_PORT);
-    bootflash_read(SPI_PORT, 0, syscfg_hdr_size, &syscfg_hdr);
+    const ssize_t result = syscfg_read(&syscfg);
 
-    if (syscfg_hdr.magic != SYSCFG_MAGIC) {
+    if (result == -1) {
         simplelist_setline("SCfg magic not found");
-        bootflash_close(SPI_PORT);
         return simplelist_show_list(&info);
     }
 
-    simplelist_addline("Total size: %lu bytes, %lu entries", syscfg_hdr.size, syscfg_hdr.num_entries);
+    simplelist_addline("Total size: %lu bytes, %lu entries", syscfg.header.size, syscfg.header.num_entries);
 
-    size_t calculated_syscfg_size = syscfg_hdr_size + syscfg_entry_size * syscfg_hdr.num_entries;
-
-    if (syscfg_hdr.size != calculated_syscfg_size) {
-        simplelist_addline("Wrong size: expected %zu, got %lu", calculated_syscfg_size, syscfg_hdr.size);
-        bootflash_close(SPI_PORT);
+    if (result > 0) {
+        simplelist_addline("Wrong size: expected %ld, got %lu", result, syscfg.header.size);
         return simplelist_show_list(&info);
     }
 
-    if (syscfg_hdr.num_entries > SYSCFG_MAX_ENTRIES) {
+    if (syscfg.header.num_entries > SYSCFG_MAX_ENTRIES) {
         simplelist_addline("Too many entries, showing only first %u", SYSCFG_MAX_ENTRIES);
     }
 
-    size_t syscfg_num_entries = MIN(syscfg_hdr.num_entries, SYSCFG_MAX_ENTRIES);
-    size_t syscfg_entries_size = syscfg_entry_size * syscfg_num_entries;
-
-    bootflash_read(SPI_PORT, syscfg_hdr_size, syscfg_entries_size, &syscfg_entries);
-    bootflash_close(SPI_PORT);
+    const size_t syscfg_num_entries = MIN(syscfg.header.num_entries, SYSCFG_MAX_ENTRIES);
 
     for (size_t i = 0; i < syscfg_num_entries; i++) {
-        struct SysCfgEntry* entry = &syscfg_entries[i];
-        char* tag = (char *)&entry->tag;
-        uint32_t* data32 = (uint32_t *)entry->data;
+        const struct SysCfgEntry* entry = &syscfg.entries[i];
+        const char* tag = (char *)&entry->tag;
+        const uint32_t* data32 = (uint32_t *)entry->data;
 
         switch (entry->tag) {
             case SYSCFG_TAG_SRNM:

firmware/target/arm/s5l8702/norboot-s5l8702.c

@@ -202,6 +202,37 @@ void bootflash_write(int port, int offset, void* addr, int size)
     }
 }
 
+/*
+ * SysCfg
+ */
+ssize_t syscfg_read(struct SysCfg* syscfg)
+{
+    const size_t syscfg_hdr_size = sizeof(struct SysCfgHeader);
+    const size_t syscfg_entry_size = sizeof(struct SysCfgEntry);
+
+    bootflash_init(SPI_PORT);
+    bootflash_read(SPI_PORT, 0, syscfg_hdr_size, &syscfg->header);
+
+    if (syscfg->header.magic != SYSCFG_MAGIC) {
+        bootflash_close(SPI_PORT);
+        return -1;
+    }
+
+    const size_t calculated_syscfg_size = syscfg_hdr_size + syscfg_entry_size * syscfg->header.num_entries;
+
+    if (syscfg->header.size != calculated_syscfg_size) {
+        bootflash_close(SPI_PORT);
+        return calculated_syscfg_size;
+    }
+
+    const size_t syscfg_num_entries = MIN(syscfg->header.num_entries, SYSCFG_MAX_ENTRIES);
+    const size_t syscfg_entries_size = syscfg_entry_size * syscfg_num_entries;
+
+    bootflash_read(SPI_PORT, syscfg_hdr_size, syscfg_entries_size, &syscfg->entries);
+    bootflash_close(SPI_PORT);
+
+    return 0;
+}
 
 /*
  * IM3

firmware/target/arm/s5l8702/norboot-target.h

@@ -23,6 +23,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include <sys/types.h>
 
 #include "config.h"
 #include "crypto-s5l8702.h"
@@ -90,6 +91,8 @@ void bootflash_close(int port);
 /*
  * SysCfg
  */
+#define SYSCFG_MAX_ENTRIES 9 // 9 on iPod Classic/6G
+
 struct SysCfgHeader {
     uint32_t magic; // always 'SCfg'
     uint32_t size;
@@ -104,6 +107,11 @@ struct SysCfgEntry {
     uint8_t data[0x10];
 };
 
+struct SysCfg {
+    struct SysCfgHeader header;
+    struct SysCfgEntry entries[SYSCFG_MAX_ENTRIES];
+};
+
 #define SYSCFG_MAGIC 0x53436667 // SCfg
 
 #define SYSCFG_TAG_SRNM 0x53724e6d // SrNm
@@ -116,6 +124,8 @@ struct SysCfgEntry {
 #define SYSCFG_TAG_MODN 0x4d6f6423 // Mod#
 #define SYSCFG_TAG_REGN 0x5265676e // Regn
 
+ssize_t syscfg_read(struct SysCfg* syscfg);
+
 /*
  * IM3
  */