[PATCH] efi/tpm: Add debug information for device protocol and eventlog

[Tianjia Zhang]

Add a number of debug logs to the tpm module. The condition tag
for opening debugging is `tpm`. On TPM machines, this will bring
great convenience to diagnosis and debugging.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
---
 grub-core/commands/efi/tpm.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/grub-core/commands/efi/tpm.c b/grub-core/commands/efi/tpm.c
index b03b6b296..49964feb9 100644
--- a/grub-core/commands/efi/tpm.c
+++ b/grub-core/commands/efi/tpm.c
@@ -56,9 +56,12 @@ grub_tpm1_present (grub_efi_tpm_protocol_t *tpm)
 
   if (status != GRUB_EFI_SUCCESS || caps.TPMDeactivatedFlag
       || !caps.TPMPresentFlag)
-    return tpm1_present = 0;
+    tpm1_present = 0;
+  else
+    tpm1_present = 1;
 
-  return tpm1_present = 1;
+  grub_dprintf ("tpm", "tpm1%s present\n", tpm1_present ? "" : " NOT");
+  return (grub_efi_boolean_t) tpm1_present;
 }
 
 static grub_efi_boolean_t
@@ -75,9 +78,12 @@ grub_tpm2_present (grub_efi_tpm2_protocol_t *tpm)
   status = efi_call_2 (tpm->get_capability, tpm, &caps);
 
   if (status != GRUB_EFI_SUCCESS || !caps.TPMPresentFlag)
-    return tpm2_present = 0;
+    tpm2_present = 0;
+  else
+    tpm2_present = 1;
 
-  return tpm2_present = 1;
+  grub_dprintf ("tpm", "tpm2%s present\n", tpm2_present ? "" : " NOT");
+  return (grub_efi_boolean_t) tpm2_present;
 }
 
 static grub_efi_boolean_t
@@ -102,6 +108,7 @@ grub_tpm_handle_find (grub_efi_handle_t *tpm_handle,
       *tpm_handle = handles[0];
       grub_tpm_version = 1;
       *protocol_version = 1;
+      grub_dprintf ("tpm", "TPM handle Found, version: 1\n");
       return 1;
     }
 
@@ -113,6 +120,7 @@ grub_tpm_handle_find (grub_efi_handle_t *tpm_handle,
       *tpm_handle = handles[0];
       grub_tpm_version = 2;
       *protocol_version = 2;
+      grub_dprintf ("tpm", "TPM handle Found, version: 2\n");
       return 1;
     }
 
@@ -231,6 +239,9 @@ grub_tpm_measure (unsigned char *buf, grub_size_t size, 
grub_uint8_t pcr,
   if (!grub_tpm_handle_find (&tpm_handle, &protocol_version))
     return 0;
 
+  grub_dprintf ("tpm", "log_event, pcr = %d, size = 0x%" PRIxGRUB_SIZE ", 
%s\n",
+                pcr, size, description);
+
   if (protocol_version == 1)
     return grub_tpm1_log_event (tpm_handle, buf, size, pcr, description);
   else
-- 
2.19.1.3.ge56e4f7