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

Message ID 20230121073741.3807-1-lina@asahilina.net
State New
Headers
Series soc: apple: rtkit: Add register dump decoding to crashlog |

Commit Message

Asahi Lina Jan. 21, 2023, 7:37 a.m. UTC
  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.

Signed-off-by: Asahi Lina <lina@asahilina.net>
---
 drivers/soc/apple/rtkit-crashlog.c | 83 ++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)
  

Comments

Sven Peter Jan. 22, 2023, 10:19 a.m. UTC | #1
On Sat, Jan 21, 2023, at 08:37, Asahi Lina wrote:
> 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.
>
> Signed-off-by: Asahi Lina <lina@asahilina.net>
> ---

Reviewed-by: Sven Peter <sven@svenpeter.dev>

thanks,

Sven
  
Eric Curtin Jan. 22, 2023, 12:16 p.m. UTC | #2
On Sat, 21 Jan 2023 at 07:48, Asahi Lina <lina@asahilina.net> wrote:
>
> 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.
>
> Signed-off-by: Asahi Lina <lina@asahilina.net>
> ---

Signed-off-by: Eric Curtin <ecurtin@redhat.com>

Is mise le meas/Regards,

Eric Curtin

>  drivers/soc/apple/rtkit-crashlog.c | 83 ++++++++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)
>
> diff --git a/drivers/soc/apple/rtkit-crashlog.c b/drivers/soc/apple/rtkit-crashlog.c
> index 732deed64660..e29ef0a80ab8 100644
> --- a/drivers/soc/apple/rtkit-crashlog.c
> +++ b/drivers/soc/apple/rtkit-crashlog.c
> @@ -13,6 +13,7 @@
>  #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')
>
>  struct apple_rtkit_crashlog_header {
>         u32 fourcc;
> @@ -31,6 +32,24 @@ 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 +113,66 @@ 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%lx", 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 +219,10 @@ 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",
> --
> 2.35.1
>
>
  
Asahi Lina Jan. 22, 2023, 5:07 p.m. UTC | #3
On 22/01/2023 19.19, Sven Peter wrote:
> On Sat, Jan 21, 2023, at 08:37, Asahi Lina wrote:
>> 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.
>>
>> Signed-off-by: Asahi Lina <lina@asahilina.net>
>> ---
> 
> Reviewed-by: Sven Peter <sven@svenpeter.dev>
> 
> thanks,
> 
> Sven

Thanks for the review! The kernel test robot complained about builds on
non-ARM64, so I'll fix that up and send a v2 ^^

~~ Lina
  
Eric Curtin Jan. 22, 2023, 6:06 p.m. UTC | #4
On Sat, 21 Jan 2023 at 07:48, Asahi Lina <lina@asahilina.net> wrote:
>
> 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.
>
> Signed-off-by: Asahi Lina <lina@asahilina.net>
> ---

Reviewed-by: Eric Curtin <ecurtin@redhat.com>

Is mise le meas/Regards,

Eric Curtin

>  drivers/soc/apple/rtkit-crashlog.c | 83 ++++++++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)
>
> diff --git a/drivers/soc/apple/rtkit-crashlog.c b/drivers/soc/apple/rtkit-crashlog.c
> index 732deed64660..e29ef0a80ab8 100644
> --- a/drivers/soc/apple/rtkit-crashlog.c
> +++ b/drivers/soc/apple/rtkit-crashlog.c
> @@ -13,6 +13,7 @@
>  #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')
>
>  struct apple_rtkit_crashlog_header {
>         u32 fourcc;
> @@ -31,6 +32,24 @@ 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 +113,66 @@ 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%lx", 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 +219,10 @@ 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",
> --
> 2.35.1
>
>
  

Patch

diff --git a/drivers/soc/apple/rtkit-crashlog.c b/drivers/soc/apple/rtkit-crashlog.c
index 732deed64660..e29ef0a80ab8 100644
--- a/drivers/soc/apple/rtkit-crashlog.c
+++ b/drivers/soc/apple/rtkit-crashlog.c
@@ -13,6 +13,7 @@ 
 #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')
 
 struct apple_rtkit_crashlog_header {
 	u32 fourcc;
@@ -31,6 +32,24 @@  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 +113,66 @@  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%lx", 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 +219,10 @@  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",