[prefix] Add .text16.early section

Add a section .text16.early which is always kept inline with the
prefix.  This will allow for some code sharing between the .prefix and
.text16 sections.

Note that the simple solution of just prepending the .prefix section
to the .text16 section will not work, because a bug in Wyse Streaming
Manager server (WLDRM13.BIN) requires us to place a dummy PXENV+ entry
point at the start of .text16.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 63 insertions, 27 deletions

diff --git a/src/arch/i386/prefix/libprefix.S b/src/arch/i386/prefix/libprefix.S
index 4decb013..b820f2a3 100644
--- a/src/arch/i386/prefix/libprefix.S
+++ b/src/arch/i386/prefix/libprefix.S
@@ -406,6 +406,7 @@ copy_bytes:
  *   %edx : total length of block (including any uninitialised data portion)
  * Returns:
  *   %esi : next source physical address (will be a multiple of 16)
+ *   %edi : next destination physical address (will be a multiple of 16)
  * Corrupts:
  *   none
  ****************************************************************************
@@ -417,7 +418,6 @@ install_block:
 	pushw	%ds
 	pushw	%es
 	pushl	%ecx
-	pushl	%edi
 	
 	/* Convert %esi and %edi to %ds:esi and %es:edi */
 	shrl	$4, %esi
@@ -445,18 +445,23 @@ install_block:
 	rep addr32 stosb
 	popw	%ax
 
-	/* Round up %esi to start of next source block */
+	/* Round up %esi and %edi to start of next blocks */
 	addl	$0xf, %esi
 	andl	$~0xf, %esi
+	addl	$0xf, %edi
+	andl	$~0xf, %edi
 
-	/* Convert %ds:esi back to a physical address */
+	/* Convert %ds:esi and %es:edi back to physical addresses */
 	xorl	%ecx, %ecx
 	movw	%ds, %cx
 	shll	$4, %ecx
 	addl	%ecx, %esi
+	xorl	%ecx, %ecx
+	movw	%es, %cx
+	shll	$4, %ecx
+	addl	%ecx, %edi
 
 	/* Restore registers and return */
-	popl	%edi
 	popl	%ecx
 	popw	%es
 	popw	%ds
@@ -626,6 +631,23 @@ install_prealloc:
 	/* Sanity: clear the direction flag asap */
 	cld
 
+	/* Copy decompression temporary area physical address to %ebp */
+	movl	%edi, %ebp
+
+	/* Install .text16.early */
+	pushl	%esi
+	xorl	%esi, %esi
+	movw	%cs, %si
+	shll	$4, %esi
+	addl	$_text16_early_lma, %esi
+	movzwl	%ax, %edi
+	shll	$4, %edi
+	movl	$_text16_early_filesz, %ecx
+	movl	$_text16_early_memsz, %edx
+	call	install_block		/* .text16.early */
+	popl	%esi
+
+	/* Open up access to payload */
 #ifndef KEEP_IT_REAL
 	/* Flatten real mode */
 	call	flatten_real_mode
@@ -636,21 +658,17 @@ install_prealloc:
 	jnz	1f
 	movw	%cs, %si
 	shll	$4, %esi
-1:	addl	$_payload_lma, %esi
+1:	addl	%cs:payload_lma, %esi
 
-	/* Install .text16 and .data16 */
-	pushl	%edi
-	movzwl	%ax, %edi
-	shll	$4, %edi
-	movl	$_text16_memsz, %ecx
-	movl	%ecx, %edx
-	call	install_block		/* .text16 */
+	/* Install .text16.late and .data16 */
+	movl	$_text16_late_filesz, %ecx
+	movl	$_text16_late_memsz, %edx
+	call	install_block		/* .text16.late */
 	movzwl	%bx, %edi
 	shll	$4, %edi
 	movl	$_data16_filesz, %ecx
 	movl	$_data16_memsz, %edx
 	call	install_block		/* .data16 */
-	popl	%edi
 
 	/* Set up %ds for access to .data16 */
 	movw	%bx, %ds
@@ -664,12 +682,14 @@ install_prealloc:
 	 * prior to reading the E820 memory map and relocating
 	 * properly.
 	 */
+	movl	%ebp, %edi
 	movl	$_textdata_filesz, %ecx
 	movl	$_textdata_memsz, %edx
 	call	install_block
 
 	/* Initialise librm at current location */
 	movw	%ax, (init_librm_vector+2)
+	movl	%ebp, %edi
 	lcall	*init_librm_vector
 
 	/* Call relocate() to determine target address for relocation.
@@ -682,13 +702,13 @@ install_prealloc:
 	popl	%edx /* discard */
 
 	/* Copy code to new location */
-	pushl	%edi
 	xorw	%ax, %ax
 	movw	%ax, %es
+	movl	%ebp, %edi
 	es rep addr32 movsb
-	popl	%edi
 
 	/* Initialise librm at new location */
+	movl	%ebp, %edi
 	lcall	*init_librm_vector
 #endif
 
@@ -719,6 +739,17 @@ prot_call_vector:
 	.size prot_call_vector, . - prot_call_vector
 #endif
 
+	/* Payload address */
+	.section ".prefix.lib", "awx", @progbits
+payload_lma:
+	.long 0
+	.section ".zinfo.fixup", "a", @progbits	/* Compressor fixups */
+	.ascii	"ADHL"
+	.long	payload_lma
+	.long	1
+	.long	0
+	.previous
+
 /****************************************************************************
  * uninstall
  *
@@ -745,27 +776,32 @@ uninstall:
 
 	/* File split information for the compressor */
 #if COMPRESS
+#define PACK_OR_COPY	"PACK"
+#else
+#define PACK_OR_COPY	"COPY"
+#endif
 	.section ".zinfo", "a", @progbits
 	.ascii	"COPY"
 	.long	_prefix_lma
 	.long	_prefix_filesz
 	.long	_max_align
-	.ascii	"PACK"
-	.long	_text16_lma
-	.long	_text16_filesz
+	.ascii	PACK_OR_COPY
+	.long	_text16_early_lma
+	.long	_text16_early_filesz
 	.long	_max_align
-	.ascii	"PACK"
+	.ascii	"PAYL"
+	.long	0
+	.long	0
+	.long	_max_align
+	.ascii	PACK_OR_COPY
+	.long	_text16_late_lma
+	.long	_text16_late_filesz
+	.long	_max_align
+	.ascii	PACK_OR_COPY
 	.long	_data16_lma
 	.long	_data16_filesz
 	.long	_max_align
-	.ascii	"PACK"
+	.ascii	PACK_OR_COPY
 	.long	_textdata_lma
 	.long	_textdata_filesz
 	.long	_max_align
-#else /* COMPRESS */
-	.section ".zinfo", "a", @progbits
-	.ascii	"COPY"
-	.long	_prefix_lma
-	.long	_filesz
-	.long	_max_align
-#endif /* COMPRESS */