arch/microblaze/kernel/kgdb.c

Source file repositories/reference/linux-study-clean/arch/microblaze/kernel/kgdb.c

File Facts

System
Linux kernel
Corpus path
arch/microblaze/kernel/kgdb.c
Extension
.c
Size
4064 bytes
Lines
153
Domain
Architecture Layer
Bucket
arch/microblaze
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#include <linux/kgdb.h>
#include <linux/kdebug.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/cacheflush.h>
#include <asm/asm-offsets.h>
#include <asm/kgdb.h>
#include <asm/pvr.h>

#define GDB_REG		0
#define GDB_PC		32
#define GDB_MSR		33
#define GDB_EAR		34
#define GDB_ESR		35
#define GDB_FSR		36
#define GDB_BTR		37
#define GDB_PVR		38
#define GDB_REDR	50
#define GDB_RPID	51
#define GDB_RZPR	52
#define GDB_RTLBX	53
#define GDB_RTLBSX	54 /* mfs can't read it */
#define GDB_RTLBLO	55
#define GDB_RTLBHI	56

/* keep pvr separately because it is unchangeable */
static struct pvr_s pvr;

void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
	unsigned int i;
	unsigned long *pt_regb = (unsigned long *)regs;
	int temp;

	/* registers r0 - r31, pc, msr, ear, esr, fsr + do not save pt_mode */
	for (i = 0; i < (sizeof(struct pt_regs) / 4) - 1; i++)
		gdb_regs[i] = pt_regb[i];

	/* Branch target register can't be changed */
	__asm__ __volatile__ ("mfs %0, rbtr;" : "=r"(temp) : );
	gdb_regs[GDB_BTR] = temp;

	/* pvr part  - we have 11 pvr regs */
	for (i = 0; i < sizeof(struct pvr_s)/4; i++)
		gdb_regs[GDB_PVR + i] = pvr.pvr[i];

	/* read special registers - can't be changed */
	__asm__ __volatile__ ("mfs %0, redr;" : "=r"(temp) : );
	gdb_regs[GDB_REDR] = temp;
	__asm__ __volatile__ ("mfs %0, rpid;" : "=r"(temp) : );
	gdb_regs[GDB_RPID] = temp;
	__asm__ __volatile__ ("mfs %0, rzpr;" : "=r"(temp) : );
	gdb_regs[GDB_RZPR] = temp;
	__asm__ __volatile__ ("mfs %0, rtlbx;" : "=r"(temp) : );
	gdb_regs[GDB_RTLBX] = temp;
	__asm__ __volatile__ ("mfs %0, rtlblo;" : "=r"(temp) : );
	gdb_regs[GDB_RTLBLO] = temp;
	__asm__ __volatile__ ("mfs %0, rtlbhi;" : "=r"(temp) : );
	gdb_regs[GDB_RTLBHI] = temp;
}

void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
	unsigned int i;
	unsigned long *pt_regb = (unsigned long *)regs;

	/* pt_regs and gdb_regs have the same 37 values.
	 * The rest of gdb_regs are unused and can't be changed.
	 * r0 register value can't be changed too. */
	for (i = 1; i < (sizeof(struct pt_regs) / 4) - 1; i++)
		pt_regb[i] = gdb_regs[i];
}

asmlinkage void microblaze_kgdb_break(struct pt_regs *regs)
{
	if (kgdb_handle_exception(1, SIGTRAP, 0, regs) != 0)
		return;

	/* Jump over the first arch_kgdb_breakpoint which is barrier to
	 * get kgdb work. The same solution is used for powerpc */
	if (*(u32 *) (regs->pc) == *(u32 *) (&arch_kgdb_ops.gdb_bpt_instr))
		regs->pc += BREAK_INSTR_SIZE;
}

/* untested */
void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
{
	unsigned int i;
	unsigned long *pt_regb = (unsigned long *)(p->thread.regs);

Annotation

Implementation Notes