Ported the memory guard debug feature to coldfire, using the breakpoint logic. There are 3 shortcomings compared to SH1: (1) While the setting itself survives RoLo, it cannot be read back because the debug module programming model is write only. (2) system_reboot() from a 'Debug' exception doesn't work because the CPU enters emulation mode, and the only way leaving this mode is via an rte instruction. (3) (fixable) Catching write accesses to the flash doesn't actually do anything because the flash memory area is set write protected in CSMR2, so a write attempt stalls the bus. * Cosmetic changes in system.c

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7600 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 137 insertions, 164 deletions

diff --git a/firmware/system.c b/firmware/system.c
index e2b4efca21..a1c48347d4 100644
--- a/firmware/system.c
+++ b/firmware/system.c
@@ -302,8 +302,15 @@ void system_init(void)
     extra_init();
 }
 
+void system_reboot (void)
+{
+}
 
-
+int system_memory_guard(int newmode)
+{
+    (void)newmode;
+    return 0;
+}
 #elif defined(CPU_COLDFIRE)
 
 #define default_interrupt(name) \
@@ -503,6 +510,67 @@ void system_init(void)
                   : : : "d0");
 }
 
+void system_reboot (void)
+{
+    set_cpu_frequency(0);
+
+    asm(" move.w #0x2700,%sr");
+    /* Reset the cookie for the crt0 crash check */
+    asm(" move.l #0,%d0");
+    asm(" move.l %d0,0x10017ffc");
+    asm(" movec.l %d0,%vbr");
+    asm(" move.l 0,%sp");
+    asm(" move.l 4,%a0");
+    asm(" jmp (%a0)");
+}
+
+/* Utilise the breakpoint hardware to catch invalid memory accesses. */
+int system_memory_guard(int newmode)
+{
+    static const unsigned long modes[MAXMEMGUARD][8] = {
+        {   /* catch nothing */
+            0x2C870000, 0x00000000, /* TDR  = 0x00000000 */
+            0x2C8D0000, 0x00000000, /* ABLR = 0x00000000 */
+            0x2C8C0000, 0x00000000, /* ABHR = 0x00000000 */
+            0x2C860000, 0x00050000, /* AATR = 0x0005 */
+        },
+        {   /* catch flash ROM writes */
+            0x2C8D0000, 0x00000000, /* ABLR = 0x00000000 */
+            0x2C8C0FFF, 0xFFFF0000, /* ABHR = 0x0FFFFFFF */
+            0x2C860000, 0x6F050000, /* AATR = 0x6F05 */
+            0x2C878000, 0x20080000, /* TDR  = 0x80002008 */
+        },
+        {   /* catch all accesses to zero area */
+            0x2C8D0000, 0x00000000, /* ABLR = 0x00000000 */
+            0x2C8C0FFF, 0xFFFF0000, /* ABHR = 0x0FFFFFFF */
+            0x2C860000, 0xEF050000, /* AATR = 0xEF05 */
+            0x2C878000, 0x20080000, /* TDR  = 0x80002008 */
+        }
+        /* Note: CPU space accesses (movec instruction), interrupt acknowledges
+           and emulator mode accesses are never caught. */
+    };
+    static int oldmode = MEMGUARD_NONE;
+
+    const unsigned long *ptr;
+    int i;
+
+    if (newmode == MEMGUARD_KEEP)
+        newmode = oldmode;
+    else
+        oldmode = newmode;
+
+    /* Always set the new mode, we don't know the old settings
+       as we cannot read back */
+    ptr = modes[newmode];
+    for (i = 0; i < 4; i++)
+    {
+        asm ( "wdebug (%0) \n" : : "a"(ptr));
+        ptr += 2;
+    }
+
+    return oldmode;
+}
+
 #ifdef IRIVER_H100
 #define MAX_REFRESH_TIMER     59
 #define NORMAL_REFRESH_TIMER  21
@@ -708,158 +776,69 @@ default_interrupt (ADITI,  109);
 /* reset vectors are handled in crt0.S */
 void (*vbr[]) (void) __attribute__ ((section (".vectors"))) = 
 {
-    /*** 4 General Illegal Instruction ***/
-
-    GII,
-
-    /*** 5 Reserved ***/
-
-    UIE5,
-
-    /*** 6 Illegal Slot Instruction ***/
-
-    ISI,
-
-    /*** 7-8 Reserved ***/
-
-    UIE7,UIE8,
-
-    /*** 9 CPU Address Error ***/
-
-    CPUAE,
-
-    /*** 10 DMA Address Error ***/
-
-    DMAAE,
-
-    /*** 11 NMI ***/
-
-    NMI,
-
-    /*** 12 User Break ***/
-
-    UB,
+    GII,       /*** 4 General Illegal Instruction ***/
+    UIE5,      /*** 5 Reserved ***/
+    ISI,       /*** 6 Illegal Slot Instruction ***/
+    UIE7,      /*** 7-8 Reserved ***/
+    UIE8,
+    CPUAE,     /*** 9 CPU Address Error ***/
+    DMAAE,     /*** 10 DMA Address Error ***/
+    NMI,       /*** 11 NMI ***/
+    UB,        /*** 12 User Break ***/
 
     /*** 13-31 Reserved ***/
+    UIE13,UIE14,UIE15,UIE16,UIE17,UIE18,UIE19,UIE20,  
+    UIE21,UIE22,UIE23,UIE24,UIE25,UIE26,UIE27,UIE28,
+    UIE29,UIE30,UIE31,
 
-    UIE13,UIE14,UIE15,UIE16,UIE17,UIE18,UIE19,UIE20,UIE21,UIE22,UIE23,UIE24,UIE25,UIE26,UIE27,UIE28,UIE29,UIE30,UIE31,
-  
     /*** 32-63 TRAPA #20...#3F ***/
+    TRAPA32,TRAPA33,TRAPA34,TRAPA35,TRAPA36,TRAPA37,TRAPA38,TRAPA39,
+    TRAPA40,TRAPA41,TRAPA42,TRAPA43,TRAPA44,TRAPA45,TRAPA46,TRAPA47,
+    TRAPA48,TRAPA49,TRAPA50,TRAPA51,TRAPA52,TRAPA53,TRAPA54,TRAPA55,
+    TRAPA56,TRAPA57,TRAPA58,TRAPA59,TRAPA60,TRAPA61,TRAPA62,TRAPA63,
 
-    TRAPA32,TRAPA33,TRAPA34,TRAPA35,TRAPA36,TRAPA37,TRAPA38,TRAPA39,TRAPA40,TRAPA41,TRAPA42,TRAPA43,TRAPA44,TRAPA45,TRAPA46,TRAPA47,TRAPA48,TRAPA49,TRAPA50,TRAPA51,TRAPA52,TRAPA53,TRAPA54,TRAPA55,TRAPA56,TRAPA57,TRAPA58,TRAPA59,TRAPA60,TRAPA61,TRAPA62,TRAPA63,
-  
     /*** 64-71 IRQ0-7 ***/ 
-
     IRQ0,IRQ1,IRQ2,IRQ3,IRQ4,IRQ5,IRQ6,IRQ7,
-  
-    /*** 72 DMAC0 ***/ 
-  
-    DEI0,
-    
-    /*** 73 Reserved ***/
-
-    UIE73,
-
-    /*** 74 DMAC1 ***/ 
-
-    DEI1,
-    
-    /*** 75 Reserved ***/
-
-    UIE75,
-
-    /*** 76 DMAC2 ***/ 
-
-    DEI2,
-    
-    /*** 77 Reserved ***/
-
-    UIE77,
-
-    /*** 78 DMAC3 ***/ 
-
-    DEI3,
-    
-    /*** 79 Reserved ***/
-
-    UIE79, 
-  
-    /*** 80-82 ITU0 ***/
-  
-    IMIA0,IMIB0,OVI0,
-    
-    /*** 83 Reserved ***/
 
-    UIE83, 
+    DEI0,      /*** 72 DMAC0 ***/
+    UIE73,     /*** 73 Reserved ***/
+    DEI1,      /*** 74 DMAC1 ***/
+    UIE75,     /*** 75 Reserved ***/
+    DEI2,      /*** 76 DMAC2 ***/
+    UIE77,     /*** 77 Reserved ***/
+    DEI3,      /*** 78 DMAC3 ***/
+    UIE79,     /*** 79 Reserved ***/
+    IMIA0,     /*** 80-82 ITU0 ***/
+    IMIB0,
+    OVI0,
+    UIE83,     /*** 83 Reserved ***/
+    IMIA1,     /*** 84-86 ITU1 ***/
+    IMIB1,
+    OVI1,
+    UIE87,     /*** 87 Reserved ***/
+    IMIA2,     /*** 88-90 ITU2 ***/
+    IMIB2,
+    OVI2,
+    UIE91,     /*** 91 Reserved ***/
+    IMIA3,     /*** 92-94 ITU3 ***/
+    IMIB3,
+    OVI3,
+    UIE95,     /*** 95 Reserved ***/
+    IMIA4,     /*** 96-98 ITU4 ***/
+    IMIB4,
+    OVI4,
+    UIE99,     /*** 99 Reserved ***/
 
-    /*** 84-86 ITU1 ***/
-  
-    IMIA1,IMIB1,OVI1,
-    
-    /*** 87 Reserved ***/
-
-    UIE87, 
-  
-    /*** 88-90 ITU2 ***/
-  
-    IMIA2,IMIB2,OVI2,
-    
-    /*** 91 Reserved ***/
-
-    UIE91, 
-  
-    /*** 92-94 ITU3 ***/
-  
-    IMIA3,IMIB3,OVI3,
-    
-    /*** 95 Reserved ***/
-
-    UIE95, 
-  
-    /*** 96-98 ITU4 ***/
-  
-    IMIA4,IMIB4,OVI4,
-    
-    /*** 99 Reserved ***/
-
-    UIE99,
-    
     /*** 100-103 SCI0 ***/ 
-  
     REI0,RXI0,TXI0,TEI0,
-  
+
     /*** 104-107 SCI1 ***/ 
-  
     REI1,RXI1,TXI1,TEI1,
-  
-    /*** 108 Parity Control Unit ***/
-  
-    UIE108,       
-  
-    /*** 109 AD Converter ***/
-  
-    ADITI
-    
-};
 
+    UIE108,    /*** 108 Parity Control Unit ***/
+    ADITI      /*** 109 AD Converter ***/
+};
 
-void system_reboot (void)
-{
-    set_irq_level(HIGHEST_IRQ_LEVEL);
-
-    asm volatile ("ldc\t%0,vbr" : : "r"(0));
-
-    PACR2 |= 0x4000; /* for coldstart detection */
-    IPRA = 0;
-    IPRB = 0;
-    IPRC = 0;
-    IPRD = 0;
-    IPRE = 0;
-    ICR = 0;
-
-    asm volatile ("jmp @%0; mov.l @%1,r15" : :
-                  "r"(*(int*)0),"r"(4));
-}
 
 void UIE (unsigned int pc) /* Unexpected Interrupt or Exception */
 {
@@ -1043,7 +1022,25 @@ void system_init(void)
     WCR3 = 0x8000; /* WAIT is pulled up, 1 state inserted for CS6 */
 }
 
-/* Utilize the user break controller to catch invalid memory accesses. */
+void system_reboot (void)
+{
+    set_irq_level(HIGHEST_IRQ_LEVEL);
+
+    asm volatile ("ldc\t%0,vbr" : : "r"(0));
+
+    PACR2 |= 0x4000; /* for coldstart detection */
+    IPRA = 0;
+    IPRB = 0;
+    IPRC = 0;
+    IPRD = 0;
+    IPRE = 0;
+    ICR = 0;
+
+    asm volatile ("jmp @%0; mov.l @%1,r15" : :
+                  "r"(*(int*)0),"r"(4));
+}
+
+/* Utilise the user break controller to catch invalid memory accesses. */
 int system_memory_guard(int newmode)
 {
     static const struct {
@@ -1087,29 +1084,5 @@ int system_memory_guard(int newmode)
     
     return oldmode;
 }
-#endif
+#endif /* CONFIG_CPU */
 
-#if CONFIG_CPU != SH7034
-/* this does nothing on non-SH systems */
-int system_memory_guard(int newmode)
-{
-    (void)newmode;
-    return 0;
-}
-
-void system_reboot (void)
-{
-#ifdef CPU_COLDFIRE
-    set_cpu_frequency(0);
-    
-    asm(" move.w #0x2700,%sr");
-    /* Reset the cookie for the crt0 crash check */
-    asm(" move.l #0,%d0");
-    asm(" move.l %d0,0x10017ffc");
-    asm(" movec.l %d0,%vbr");
-    asm(" move.l 0,%sp");
-    asm(" move.l 4,%a0");
-    asm(" jmp (%a0)");
-#endif
-}
-#endif