Commit 22991d8d authored by Asahi Lina's avatar Asahi Lina Committed by Hector Martin
Browse files

soc: apple: rtkit: Add register dump decoding to crashlog 



When the coprocessor crashes, it's useful to get a proper register dump
so we can find out what the firmware was doing. Add a decoder for this.

Originally this had ESR decoding by reusing the ARM64 arch header for
this, but that introduces some module linking and cross-arch compilation
issues, so let's leave that out for now.

Reviewed-by: default avatarSven Peter <sven@svenpeter.dev>
Reviewed-by: default avatarEric Curtin <ecurtin@redhat.com>
Signed-off-by: default avatarAsahi Lina <lina@asahilina.net>
Signed-off-by: default avatarHector Martin <marcan@marcan.st>
parent b3892860

drivers/soc/apple/rtkit-crashlog.c

+93 −0
Original line number Diff line number Diff line
@@ -13,6 +13,17 @@ 
#define APPLE_RTKIT_CRASHLOG_VERSION FOURCC('C', 'v', 'e', 'r')

#define APPLE_RTKIT_CRASHLOG_MBOX FOURCC('C', 'm', 'b', 'x')

#define APPLE_RTKIT_CRASHLOG_TIME FOURCC('C', 't', 'i', 'm')

#define APPLE_RTKIT_CRASHLOG_REGS FOURCC('C', 'r', 'g', '8')



/* For COMPILE_TEST on non-ARM64 architectures */

#ifndef PSR_MODE_EL0t

#define PSR_MODE_EL0t	0x00000000

#define PSR_MODE_EL1t	0x00000004

#define PSR_MODE_EL1h	0x00000005

#define PSR_MODE_EL2t	0x00000008

#define PSR_MODE_EL2h	0x00000009

#define PSR_MODE_MASK	0x0000000f

#endif



struct apple_rtkit_crashlog_header {

	u32 fourcc;
@@ -31,6 +42,24 @@ struct apple_rtkit_crashlog_mbox_entry { 
};

static_assert(sizeof(struct apple_rtkit_crashlog_mbox_entry) == 0x18);



struct apple_rtkit_crashlog_regs {

	u32 unk_0;

	u32 unk_4;

	u64 regs[31];

	u64 sp;

	u64 pc;

	u64 psr;

	u64 cpacr;

	u64 fpsr;

	u64 fpcr;

	u64 unk[64];

	u64 far;

	u64 unk_X;

	u64 esr;

	u64 unk_Z;

};

static_assert(sizeof(struct apple_rtkit_crashlog_regs) == 0x350);



static void apple_rtkit_crashlog_dump_str(struct apple_rtkit *rtk, u8 *bfr,

					  size_t size)

{
@@ -94,6 +123,66 @@ static void apple_rtkit_crashlog_dump_mailbox(struct apple_rtkit *rtk, u8 *bfr, 
	}

}



static void apple_rtkit_crashlog_dump_regs(struct apple_rtkit *rtk, u8 *bfr,

					   size_t size)

{

	struct apple_rtkit_crashlog_regs regs;

	const char *el;

	int i;



	if (size < sizeof(regs)) {

		dev_warn(rtk->dev, "RTKit: Regs section too small: 0x%zx", size);

		return;

	}



	memcpy(&regs, bfr, sizeof(regs));



	switch (regs.psr & PSR_MODE_MASK) {

	case PSR_MODE_EL0t:

		el = "EL0t";

		break;

	case PSR_MODE_EL1t:

		el = "EL1t";

		break;

	case PSR_MODE_EL1h:

		el = "EL1h";

		break;

	case PSR_MODE_EL2t:

		el = "EL2t";

		break;

	case PSR_MODE_EL2h:

		el = "EL2h";

		break;

	default:

		el = "unknown";

		break;

	}



	dev_warn(rtk->dev, "RTKit: Exception dump:");

	dev_warn(rtk->dev, "  == Exception taken from %s ==", el);

	dev_warn(rtk->dev, "  PSR    = 0x%llx", regs.psr);

	dev_warn(rtk->dev, "  PC     = 0x%llx\n", regs.pc);

	dev_warn(rtk->dev, "  ESR    = 0x%llx\n", regs.esr);

	dev_warn(rtk->dev, "  FAR    = 0x%llx\n", regs.far);

	dev_warn(rtk->dev, "  SP     = 0x%llx\n", regs.sp);

	dev_warn(rtk->dev, "\n");



	for (i = 0; i < 31; i += 4) {

		if (i < 28)

			dev_warn(rtk->dev,

					 "  x%02d-x%02d = %016llx %016llx %016llx %016llx\n",

					 i, i + 3,

					 regs.regs[i], regs.regs[i + 1],

					 regs.regs[i + 2], regs.regs[i + 3]);

		else

			dev_warn(rtk->dev,

					 "  x%02d-x%02d = %016llx %016llx %016llx\n", i, i + 3,

					 regs.regs[i], regs.regs[i + 1], regs.regs[i + 2]);

	}



	dev_warn(rtk->dev, "\n");

}



void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size)

{

	size_t offset;
@@ -140,6 +229,10 @@ void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size) 
			apple_rtkit_crashlog_dump_time(rtk, bfr + offset + 16,

						       section_size);

			break;

		case APPLE_RTKIT_CRASHLOG_REGS:

			apple_rtkit_crashlog_dump_regs(rtk, bfr + offset + 16,

						       section_size);

			break;

		default:

			dev_warn(rtk->dev,

				 "RTKit: Unknown crashlog section: %x",