Initial revision

1 files changed, 309 insertions, 0 deletions

diff --git a/cpu/ppc4xx/bedbug_405.c b/cpu/ppc4xx/bedbug_405.c
new file mode 100644
index 0000000..eabc583
--- /dev/null
+++ b/cpu/ppc4xx/bedbug_405.c
@@ -0,0 +1,309 @@
+/*
+ * Bedbug Functions specific to the PPC405 chip
+ */
+
+#include <common.h>
+#include <command.h>
+#include <linux/ctype.h>
+
+#include <cmd_bedbug.h>
+#include <bedbug/bedbug.h>
+#include <bedbug/regs.h>
+#include <bedbug/ppc.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG) && defined(CONFIG_4xx)
+
+#define MAX_BREAK_POINTS 4
+
+extern CPU_DEBUG_CTX bug_ctx;
+
+void bedbug405_init __P ((void));
+void bedbug405_do_break __P ((cmd_tbl_t *, int, int, char *[]));
+void bedbug405_break_isr __P ((struct pt_regs *));
+int bedbug405_find_empty __P ((void));
+int bedbug405_set __P ((int, unsigned long));
+int bedbug405_clear __P ((int));
+
+
+/* ======================================================================
+ * Initialize the global bug_ctx structure for the IBM PPC405.	Clear all
+ * of the breakpoints.
+ * ====================================================================== */
+
+void bedbug405_init (void)
+{
+	int i;
+
+	/* -------------------------------------------------- */
+
+	bug_ctx.hw_debug_enabled = 0;
+	bug_ctx.stopped = 0;
+	bug_ctx.current_bp = 0;
+	bug_ctx.regs = NULL;
+
+	bug_ctx.do_break = bedbug405_do_break;
+	bug_ctx.break_isr = bedbug405_break_isr;
+	bug_ctx.find_empty = bedbug405_find_empty;
+	bug_ctx.set = bedbug405_set;
+	bug_ctx.clear = bedbug405_clear;
+
+	for (i = 1; i <= MAX_BREAK_POINTS; ++i)
+		(*bug_ctx.clear) (i);
+
+	puts ("BEDBUG:ready\n");
+	return;
+}	/* bedbug_init_breakpoints */
+
+
+
+/* ======================================================================
+ * Set/clear/show one of the hardware breakpoints for the 405.	The "off"
+ * string will disable a specific breakpoint.  The "show" string will
+ * display the current breakpoints.  Otherwise an address will set a
+ * breakpoint at that address.	Setting a breakpoint uses the CPU-specific
+ * set routine which will assign a breakpoint number.
+ * ====================================================================== */
+
+void bedbug405_do_break (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+{
+	long addr = 0;		/* Address to break at  */
+	int which_bp;		/* Breakpoint number    */
+
+	/* -------------------------------------------------- */
+
+	if (argc < 2) {
+		printf ("Usage:\n%s\n", cmdtp->usage);
+		return;
+	}
+
+	/* Turn off a breakpoint */
+
+	if (strcmp (argv[1], "off") == 0) {
+		if (bug_ctx.hw_debug_enabled == 0) {
+			printf ("No breakpoints enabled\n");
+			return;
+		}
+
+		which_bp = simple_strtoul (argv[2], NULL, 10);
+
+		if (bug_ctx.clear)
+			(*bug_ctx.clear) (which_bp);
+
+		printf ("Breakpoint %d removed\n", which_bp);
+		return;
+	}
+
+	/* Show a list of breakpoints */
+
+	if (strcmp (argv[1], "show") == 0) {
+		for (which_bp = 1; which_bp <= MAX_BREAK_POINTS; ++which_bp) {
+
+			switch (which_bp) {
+			case 1:
+				addr = GET_IAC1 ();
+				break;
+			case 2:
+				addr = GET_IAC2 ();
+				break;
+			case 3:
+				addr = GET_IAC3 ();
+				break;
+			case 4:
+				addr = GET_IAC4 ();
+				break;
+			}
+
+			printf ("Breakpoint [%d]: ", which_bp);
+			if (addr == 0)
+				printf ("NOT SET\n");
+			else
+				disppc ((unsigned char *) addr, 0, 1, bedbug_puts,
+						F_RADHEX);
+		}
+		return;
+	}
+
+	/* Set a breakpoint at the address */
+
+	if (!isdigit (argv[1][0])) {
+		printf ("Usage:\n%s\n", cmdtp->usage);
+		return;
+	}
+
+	addr = simple_strtoul (argv[1], NULL, 16) & 0xfffffffc;
+
+	if ((bug_ctx.set) && (which_bp = (*bug_ctx.set) (0, addr)) > 0) {
+		printf ("Breakpoint [%d]: ", which_bp);
+		disppc ((unsigned char *) addr, 0, 1, bedbug_puts, F_RADHEX);
+	}
+
+	return;
+}	/* bedbug405_do_break */
+
+
+
+/* ======================================================================
+ * Handle a breakpoint.	 First determine which breakpoint was hit by
+ * looking at the DeBug Status Register (DBSR), clear the breakpoint
+ * and enter a mini main loop.	Stay in the loop until the stopped flag
+ * in the debug context is cleared.
+ * ====================================================================== */
+
+void bedbug405_break_isr (struct pt_regs *regs)
+{
+	unsigned long dbsr_val;		/* Value of the DBSR    */
+	unsigned long addr = 0;		/* Address stopped at   */
+
+	/* -------------------------------------------------- */
+
+	dbsr_val = GET_DBSR ();
+
+	if (dbsr_val & DBSR_IA1) {
+		bug_ctx.current_bp = 1;
+		addr = GET_IAC1 ();
+		SET_DBSR (DBSR_IA1);	/* Write a 1 to clear */
+	} else if (dbsr_val & DBSR_IA2) {
+		bug_ctx.current_bp = 2;
+		addr = GET_IAC2 ();
+		SET_DBSR (DBSR_IA2);	/* Write a 1 to clear */
+	} else if (dbsr_val & DBSR_IA3) {
+		bug_ctx.current_bp = 3;
+		addr = GET_IAC3 ();
+		SET_DBSR (DBSR_IA3);	/* Write a 1 to clear */
+	} else if (dbsr_val & DBSR_IA4) {
+		bug_ctx.current_bp = 4;
+		addr = GET_IAC4 ();
+		SET_DBSR (DBSR_IA4);	/* Write a 1 to clear */
+	}
+
+	bedbug_main_loop (addr, regs);
+	return;
+}	/* bedbug405_break_isr */
+
+
+
+/* ======================================================================
+ * Look through all of the hardware breakpoints available to see if one
+ * is unused.
+ * ====================================================================== */
+
+int bedbug405_find_empty (void)
+{
+	/* -------------------------------------------------- */
+
+	if (GET_IAC1 () == 0)
+		return 1;
+
+	if (GET_IAC2 () == 0)
+		return 2;
+
+	if (GET_IAC3 () == 0)
+		return 3;
+
+	if (GET_IAC4 () == 0)
+		return 4;
+
+	return 0;
+}	/* bedbug405_find_empty */
+
+
+
+/* ======================================================================
+ * Set a breakpoint.  If 'which_bp' is zero then find an unused breakpoint
+ * number, otherwise reassign the given breakpoint.  If hardware debugging
+ * is not enabled, then turn it on via the MSR and DBCR0.  Set the break
+ * address in the appropriate IACx register and enable proper address
+ * beakpoint in DBCR0.
+ * ====================================================================== */
+
+int bedbug405_set (int which_bp, unsigned long addr)
+{
+	/* -------------------------------------------------- */
+
+	/* Only look if which_bp == 0, else use which_bp */
+	if ((bug_ctx.find_empty) && (!which_bp) &&
+		(which_bp = (*bug_ctx.find_empty) ()) == 0) {
+		printf ("All breakpoints in use\n");
+		return 0;
+	}
+
+	if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
+		printf ("Invalid break point # %d\n", which_bp);
+		return 0;
+	}
+
+	if (!bug_ctx.hw_debug_enabled) {
+		SET_MSR (GET_MSR () | 0x200);	/* set MSR[ DE ] */
+		SET_DBCR0 (GET_DBCR0 () | DBCR0_IDM);
+		bug_ctx.hw_debug_enabled = 1;
+	}
+
+	switch (which_bp) {
+	case 1:
+		SET_IAC1 (addr);
+		SET_DBCR0 (GET_DBCR0 () | DBCR0_IA1);
+		break;
+
+	case 2:
+		SET_IAC2 (addr);
+		SET_DBCR0 (GET_DBCR0 () | DBCR0_IA2);
+		break;
+
+	case 3:
+		SET_IAC3 (addr);
+		SET_DBCR0 (GET_DBCR0 () | DBCR0_IA3);
+		break;
+
+	case 4:
+		SET_IAC4 (addr);
+		SET_DBCR0 (GET_DBCR0 () | DBCR0_IA4);
+		break;
+	}
+
+	return which_bp;
+}	/* bedbug405_set */
+
+
+
+/* ======================================================================
+ * Disable a specific breakoint by setting the appropriate IACx register
+ * to zero and claring the instruction address breakpoint in DBCR0.
+ * ====================================================================== */
+
+int bedbug405_clear (int which_bp)
+{
+	/* -------------------------------------------------- */
+
+	if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
+		printf ("Invalid break point # (%d)\n", which_bp);
+		return -1;
+	}
+
+	switch (which_bp) {
+	case 1:
+		SET_IAC1 (0);
+		SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA1);
+		break;
+
+	case 2:
+		SET_IAC2 (0);
+		SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA2);
+		break;
+
+	case 3:
+		SET_IAC3 (0);
+		SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA3);
+		break;
+
+	case 4:
+		SET_IAC4 (0);
+		SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA4);
+		break;
+	}
+
+	return 0;
+}	/* bedbug405_clear */
+
+
+/* ====================================================================== */
+#endif