separate status into fields governed by MCU and by SNES

Avoid status getting overwritten by race conditions

snes/memmap.i65

@@ -50,7 +50,8 @@
 
 #define FILESEL_CWD                 $FF0000
 #define CFG_ADDR                    $FF0100
-#define ST_ADDR                     $FF1100
+#define ST_MCU_ADDR                 $FF1100
+#define ST_SNES_ADDR                $FF1110
 #define SYSINFO_BLK                 $FF1200
 #define LAST_GAME                   $FF1420
 #define WRAM_BAK                    $FF2000
@@ -107,12 +108,13 @@
 
 #define MENU_ENTRY_SIZE             23
 
-#define ST_RTC_VALID                ST_ADDR+$0000
-#define ST_NUM_RECENT_GAMES         ST_ADDR+$0001
-#define ST_IS_U16                   ST_ADDR+$0002
-#define ST_U16_CFG                  ST_ADDR+$0003
-#define ST_PAIRMODE                 ST_ADDR+$0004
-#define ST_HAS_SATELLAVIEW          ST_ADDR+$0005
+#define ST_RTC_VALID                ST_MCU_ADDR+$0000
+#define ST_NUM_RECENT_GAMES         ST_MCU_ADDR+$0001
+#define ST_PAIRMODE                 ST_MCU_ADDR+$0002
+
+#define ST_IS_U16                   ST_SNES_ADDR+$0000
+#define ST_U16_CFG                  ST_SNES_ADDR+$0001
+#define ST_HAS_SATELLAVIEW          ST_SNES_ADDR+$0002
 
 #define MTYPE_FUNC                  $01
 #define MTYPE_SUBMENU               $02

src/cfg.c

@@ -38,7 +38,7 @@ cfg_t CFG_DEFAULT = {
 };
 
 cfg_t CFG;
-extern status_t ST;
+extern mcu_status_t STM;
 
 int cfg_save() {
   int err = 0;
@@ -277,7 +277,7 @@ void cfg_dump_recent_games_for_snes(uint32_t address) {
     f_gets(fntmp, 255, &file_handle);
     sram_writestrn(strrchr((const char*)fntmp, '/')+1, address+256*index, 256);
   }
-  ST.num_recent_games = index;
+  STM.num_recent_games = index;
   file_close();
 }
 

src/main.c

@@ -47,7 +47,8 @@ extern snes_romprops_t romprops;
 extern volatile int reset_changed;
 
 extern volatile cfg_t CFG;
-extern volatile status_t ST;
+extern volatile mcu_status_t STM;
+extern volatile snes_status_t STS;
 
 void menu_cmd_readdir(void) {
   uint8_t path[256];
@@ -180,21 +181,21 @@ printf("PCONP=%lx\n", LPC_SC->PCONP);
 
     if((rtc_state = rtc_isvalid()) != RTC_OK) {
       printf("RTC invalid!\n");
-      ST.rtc_valid = 0xff;
+      STM.rtc_valid = 0xff;
       set_bcdtime(0x20120701000000LL);
       set_fpga_time(0x20120701000000LL);
       invalidate_rtc();
     } else {
       printf("RTC valid!\n");
-      ST.rtc_valid = 0;
+      STM.rtc_valid = 0;
       set_fpga_time(get_bcdtime());
     }
     sram_memset(SRAM_SYSINFO_ADDR, 13*40, 0x20);
     printf("SNES GO!\n");
     snes_reset(1);
     fpga_reset_srtc_state();
     if(!firstboot) {
-      if(ST.is_u16 && (ST.u16_cfg & 0x01)) {
+      if(STS.is_u16 && (STS.u16_cfg & 0x01)) {
         delay_ms(59*SNES_RESET_PULSELEN_MS);
       }
     }
@@ -204,15 +205,15 @@ printf("PCONP=%lx\n", LPC_SC->PCONP);
     enum cicstates cic_state = get_cic_state();
     switch(cic_state) {
       case CIC_PAIR:
-        ST.pairmode = 1;
+        STM.pairmode = 1;
         printf("PAIR MODE ENGAGED!\n");
         cic_pair(CFG.vidmode_menu, CFG.vidmode_menu);
         break;
       case CIC_SCIC:
-        ST.pairmode = 1;
+        STM.pairmode = 1;
         break;
       default:
-        ST.pairmode = 0;
+        STM.pairmode = 0;
     }
     fpga_set_dac_boost(CFG.msu_volume_boost);
     cfg_load_to_menu();

src/memory.c

@@ -57,7 +57,7 @@ extern uint32_t saveram_crc_old;
 extern uint8_t sram_crc_valid;
 extern uint32_t sram_crc_romsize;
 extern cfg_t CFG;
-extern status_t ST;
+extern snes_status_t STS;
 
 void sram_hexdump(uint32_t addr, uint32_t len) {
   static uint8_t buf[16];
@@ -364,7 +364,7 @@ uint32_t load_rom(uint8_t* filename, uint32_t base_addr, uint8_t flags) {
   }
   printf("done\n");
 
-  if(cfg_is_r213f_override_enabled() && (filename != (uint8_t*)MENU_FILENAME) && !ST.is_u16) {
+  if(cfg_is_r213f_override_enabled() && (filename != (uint8_t*)MENU_FILENAME) && !STS.is_u16) {
     romprops.fpga_features |= FEAT_213F; /* e.g. for general consoles */
   }
   fpga_set_213f(romprops.region);
@@ -390,7 +390,7 @@ uint32_t load_rom(uint8_t* filename, uint32_t base_addr, uint8_t flags) {
   romprops.fpga_features |= FEAT_2100_LIMIT(cfg_get_brightness_limit());
 
   /* enable Satellaview Base emulation only if no physical Satellaview Base unit is present */
-  if(!ST.has_satellaview) {
+  if(!STS.has_satellaview) {
     romprops.fpga_features |= FEAT_SATELLABASE;
   }
 
@@ -405,7 +405,7 @@ uint32_t load_rom(uint8_t* filename, uint32_t base_addr, uint8_t flags) {
     printf("resetting SNES\n");
     fpga_dspx_reset(1);
     snes_reset(1);
-    if(ST.is_u16 && (ST.u16_cfg & 0x01)) {
+    if(STS.is_u16 && (STS.u16_cfg & 0x01)) {
       delay_ms(60*SNES_RESET_PULSELEN_MS);
     } else {
       delay_ms(SNES_RESET_PULSELEN_MS);

src/memory.h

@@ -50,7 +50,8 @@
 #define SRAM_MENU_CFG_ADDR      (0xFF0100L)
 #define SRAM_CMD_ADDR           (0xFF1000L)
 #define SRAM_PARAM_ADDR         (0xFF1004L)
-#define SRAM_STATUS_ADDR        (0xFF1100L)
+#define SRAM_MCU_STATUS_ADDR    (0xFF1100L)
+#define SRAM_SNES_STATUS_ADDR   (0xFF1110L)
 #define SRAM_SYSINFO_ADDR       (0xFF1200L)
 #define SRAM_LASTGAME_ADDR      (0xFF1420L)
 #define SRAM_SCRATCHPAD         (0xFFFF00L)

src/snes.c

@@ -53,9 +53,13 @@ extern cfg_t CFG;
 volatile int reset_changed;
 volatile int reset_pressed;
 
-status_t ST = {
+mcu_status_t STM = {
   .rtc_valid = 0xff,
   .num_recent_games = 0,
+  .pairmode = 0
+};
+
+snes_status_t STS = {
   .is_u16 = 0,
   .u16_cfg = 0xff,
   .has_satellaview = 0
@@ -480,11 +484,11 @@ void snescmd_prepare_nmihook() {
 }
 
 void status_load_to_menu() {
-  sram_writeblock(&ST, SRAM_STATUS_ADDR, sizeof(status_t));
+  sram_writeblock(&STM, SRAM_MCU_STATUS_ADDR, sizeof(mcu_status_t));
 }
 
 void status_save_from_menu() {
-  sram_readblock(&ST, SRAM_STATUS_ADDR, sizeof(status_t));
+  sram_readblock(&STS, SRAM_SNES_STATUS_ADDR, sizeof(snes_status_t));
 }
 
 /*

src/snes.h

@@ -96,14 +96,17 @@
 
 enum snes_reset_state { SNES_RESET_NONE = 0, SNES_RESET_SHORT, SNES_RESET_LONG };
 
-typedef struct __attribute__ ((__packed__)) _status {
+typedef struct __attribute__ ((__packed__)) _mcu_status {
   uint8_t rtc_valid;
   uint8_t num_recent_games;
+  uint8_t pairmode;
+} mcu_status_t;
+
+typedef struct __attribute__ ((__packed__)) _snes_status {
   uint8_t is_u16;
   uint8_t u16_cfg;
-  uint8_t pairmode;
   uint8_t has_satellaview;
-} status_t;
+} snes_status_t;
 
 uint8_t crc_valid;
 

src/sysinfo.c

@@ -15,7 +15,7 @@
 #include "sdnative.h"
 #include "sysinfo.h"
 
-extern status_t ST;
+extern snes_status_t STS;
 
 static uint32_t sd_tacc_max, sd_tacc_avg;
 
@@ -116,11 +116,11 @@ int write_sysinfo(int sd_measured) {
   memset(linebuf+len, 0x20, 40-len);
   sram_writeblock(linebuf, sram_addr, 40);
   sram_addr += 40;
-  if(ST.is_u16) {
-    if(ST.u16_cfg & 0x01) {
-      len = snprintf(linebuf, sizeof(linebuf), "Ultra16 serial no. %d (Autoboot On)", ST.is_u16);
+  if(STS.is_u16) {
+    if(STS.u16_cfg & 0x01) {
+      len = snprintf(linebuf, sizeof(linebuf), "Ultra16 serial no. %d (Autoboot On)", STS.is_u16);
     } else {
-      len = snprintf(linebuf, sizeof(linebuf), "Ultra16 serial no. %d (Autoboot Off)", ST.is_u16);
+      len = snprintf(linebuf, sizeof(linebuf), "Ultra16 serial no. %d (Autoboot Off)", STS.is_u16);
     }
     memset(linebuf+len, 0x20, 40-len);
     sram_writeblock(linebuf, sram_addr, 40);