More precise error messages

README.md

@@ -364,12 +364,18 @@ BOOTBOOT-PANIC: Unable to initialize SDHC card
 
 The loader was unable to initialize EMMC for SDHC card access, probably hardware error or old card.
 
+```
+BOOTBOOT-PANIC: No GPT found
+```
+
+The loader was unable to load the GUID Partitioning Table.
+
 ```
 BOOTBOOT-PANIC: No boot partition
 ```
 
-Either the disk does not have a GPT, or there's no EFI System Partition nor any other bootable
+There's no EFI System Partition nor any other bootable partition in the GPT. Or the FAT file system is found but corrupt
-partition on it. Or the FAT file system is found but inconsistent, or doesn't have a BOOTBOOT directory.
+(contains inconsistent BPB data), or doesn't have a BOOTBOOT directory (with 8+3 MSDOS entry, not LFN).
 
 ```
 BOOTBOOT-PANIC: Not 2048 sector aligned

aarch64-rpi/bootboot.c

@@ -1218,8 +1218,8 @@ int bootboot_main(uint64_t hcl)
     /* read and parse GPT table */
     r=sd_readblock(1,(unsigned char*)&__diskbuf,1);
     if(r==0 || memcmp((void*)&__diskbuf, "EFI PART", 8)) {
-diskerr:
+gpterr:
-        puts("BOOTBOOT-PANIC: No boot partition\n");
+        puts("BOOTBOOT-PANIC: No GPT found\n");
         goto error;
     }
     // get number of partitions and size of partition entry
@@ -1227,7 +1227,7 @@ diskerr:
     if(np>127) np=127;
     // read GPT entries
     r=sd_readblock(*((uint32_t*)((char*)&__diskbuf+72)),(unsigned char*)&__diskbuf,(np*sp+511)/512);
-    if(r==0) goto diskerr;
+    if(r==0) goto gpterr;
     part=NULL;
     // first, look for a partition with bootable flag
     for(r=0;r<np;r++) {
@@ -1254,7 +1254,11 @@ diskerr:
                 break;
         }
     }
-    if(part==NULL || r>=np) goto diskerr;
+    if(part==NULL || r>=np) {
+diskerr:
+        puts("BOOTBOOT-PANIC: No boot partition\n");
+        goto error;
+    }
     r=sd_readblock(part->start,(unsigned char*)&_end,1);
     if(r==0) goto diskerr;
     initrd.ptr=NULL; initrd.size=0;

x86_64-bios/bootboot.asm

@@ -1040,7 +1040,7 @@ end if
             mov         esi, 0A000h+512
             cmp         dword [esi], 'EFI '
             je          @f
-.nogpt:     mov         si, nogpt
+.nogpt:     mov         esi, nogpt
             jmp         prot_diefunc
 @@:         mov         edi, 0B000h
             mov         ebx, edi
@@ -1084,8 +1084,8 @@ end if
 .noto:      add         esi, ebx
             dec         ecx
             jnz         @b
-.noinitrd:  mov         esi, nord
+.nopart:    mov         esi, nopar
-            jz          prot_diefunc
+            jmp         prot_diefunc
 
             ; load ESP at free memory hole found
 .loadesp:   mov         dword [gpt_ptr], esi
@@ -1112,9 +1112,9 @@ end if
             je          .isfat
             ;no, then it's an initrd on the entire partition
             or          eax, eax
-            jz          .noinitrd
+            jz          .nopart
             or          ecx, ecx
-            jz          .noinitrd
+            jz          .nopart
             sub         ecx, eax
             shl         ecx, 9
             mov         dword [bootboot.initrd_size], ecx
@@ -1325,6 +1325,8 @@ end if
             jz          .loadinitrd
             dec         ecx
             jnz         .nextdir
+.noinitrd:  mov         esi, nord
+            jmp         prot_diefunc
 
             ;load cluster chain, eax=cluster, ecx=size
 .loadinitrd:
@@ -2571,7 +2573,8 @@ memerr:     db          "E820 memory map not found",0
 nogzmem:    db          "Inflating: "
 noenmem:    db          "Not enough memory",0
 noacpi:     db          "ACPI not found",0
-nogpt:      db          "No boot partition",0
+nogpt:      db          "No GPT found",0
+nopar:      db          "No boot partition",0
 nord:       db          "Initrd not found",0
 nolib:      db          "/sys not found in initrd",0
 nocore:     db          "Kernel not found in initrd",0

x86_64-efi/bootboot.c

@@ -1256,7 +1256,7 @@ efi_main (EFI_HANDLE image, EFI_SYSTEM_TABLE *systab)
     EFI_PROCESSOR_INFORMATION *pibuf=(EFI_PROCESSOR_INFORMATION*)pibuffer;
     UINTN bsp_num=0, i, j=0, handle_size=0,memory_map_size=0, map_key=0, desc_size=0;
     UINT32 desc_version=0;
-    UINT64 lba_s=0,lba_e=0;
+    UINT64 lba_s=0,lba_e=0,sysptr;
     MMapEnt *mmapent, *last=NULL;
     file_t ret={NULL,0};
     CHAR16 **argv, *initrdfile, *configfile, *help=
@@ -1550,9 +1550,9 @@ gzerr:          return report(EFI_COMPROMISED_DATA,L"Unable to uncompress");
 
         // System tables and structures
         DBG(L" * System tables%s\n",L"");
-        LibGetSystemConfigurationTable(&AcpiTableGuid,(void *)&(bootboot->arch.x86_64.acpi_ptr));
+        sysptr = 0; LibGetSystemConfigurationTable(&AcpiTableGuid,(void *)&sysptr); bootboot->arch.x86_64.acpi_ptr = sysptr;
-        LibGetSystemConfigurationTable(&SMBIOSTableGuid,(void *)&(bootboot->arch.x86_64.smbi_ptr));
+        sysptr = 0; LibGetSystemConfigurationTable(&SMBIOSTableGuid,(void *)&sysptr); bootboot->arch.x86_64.smbi_ptr = sysptr;
-        LibGetSystemConfigurationTable(&MpsTableGuid,(void *)&(bootboot->arch.x86_64.mp_ptr));
+        sysptr = 0; LibGetSystemConfigurationTable(&MpsTableGuid,(void *)&sysptr); bootboot->arch.x86_64.mp_ptr = sysptr;
 
         // FIX ACPI table pointer on TianoCore...
         ret.ptr = (UINT8*)(bootboot->arch.x86_64.acpi_ptr);