Separate out pxe_start_nbp() from pxe_image.c into pxe_call.c

Implement PXENV_RESTART_TFTP.

src/arch/i386/image/pxe_image.c

 #include <gpxe/segment.h>
 #include <gpxe/netdevice.h>
 
-/** PXE load address segment */
-#define PXE_LOAD_SEGMENT 0
-
-/** PXE load address offset */
-#define PXE_LOAD_OFFSET 0x7c00
-
 struct image_type pxe_image_type __image_type ( PROBE_PXE );
 
 /**
  */
 static int pxe_exec ( struct image *image __unused ) {
 	struct net_device *netdev;
-	int discard_b, discard_c;
-	uint16_t rc;
 
 	/* Ensure that PXE stack is ready to use */
 	pxe_init_structures();
 		break;
 	}
 
-	/* Far call to PXE NBP */
-	__asm__ __volatile__ ( REAL_CODE ( "pushw %%cx\n\t"
-					   "pushw %%ax\n\t"
-					   "movw %%cx, %%es\n\t"
-					   "lcall $0, $0x7c00\n\t"
-					   "addw $4, %%sp\n\t" )
-			       : "=a" ( rc ), "=b" ( discard_b ),
-			         "=c" ( discard_c )
-			       :  "a" ( & __from_text16 ( ppxe ) ),
-			          "b" ( & __from_text16 ( pxenv ) ),
-			          "c" ( rm_cs )
-			       : "edx", "esi", "edi", "ebp", "memory" );
-
-	return rc;
+	return pxe_start_nbp();
 }
 
 /**

src/arch/i386/include/pxe_call.h

 #include <pxe_api.h>
 #include <realmode.h>
 
+/** PXE load address segment */
+#define PXE_LOAD_SEGMENT 0
+
+/** PXE load address offset */
+#define PXE_LOAD_OFFSET 0x7c00
+
+/** PXE physical load address */
+#define PXE_LOAD_PHYS ( ( PXE_LOAD_SEGMENT << 4 ) + PXE_LOAD_OFFSET )
+
 /** !PXE structure */
 extern struct s_PXE __text16 ( ppxe );
 #define ppxe __use_text16 ( ppxe )
 extern void pxe_hook_int1a ( void );
 extern int pxe_unhook_int1a ( void );
 extern void pxe_init_structures ( void );
+extern int pxe_start_nbp ( void );
 
 #endif /* _PXE_CALL_H */

src/arch/i386/include/pxe_callbacks.h

-/* Header for pxe_callbacks.c.
- */
-
-#ifndef PXE_CALLBACKS_H
-#define PXE_CALLBACKS_H
-
-#include "etherboot.h"
-#include "pxe_types.h"
-
-typedef struct {
-	SEGOFF16_t	orig_retaddr;
-	UINT16_t	opcode;
-	SEGOFF16_t	segoff;
-} PACKED pxe_call_params_t;
-
-/*
- * These values are hard-coded into the PXE spec
- */
-#define PXE_LOAD_SEGMENT	(0x0000)
-#define PXE_LOAD_OFFSET		(0x7c00)
-#define PXE_LOAD_ADDRESS	( ( PXE_LOAD_SEGMENT << 4 ) + PXE_LOAD_OFFSET )
-
-/* Function prototypes
- */
-extern struct pxe_stack * install_pxe_stack ( void *base );
-extern void use_undi_ds_for_rm_stack ( uint16_t ds );
-extern int hook_pxe_stack ( void );
-extern int unhook_pxe_stack ( void );
-extern void remove_pxe_stack ( void );
-extern int xstartpxe ( void );
-
-#endif /* PXE_CALLBACKS_H */

src/arch/i386/interface/pxe/pxe_call.c

 	ppxe.StructCksum -= pxe_checksum ( &ppxe, sizeof ( ppxe ) );
 	pxenv.Checksum -= pxe_checksum ( &pxenv, sizeof ( pxenv ) );
 }
+
+/**
+ * Start PXE NBP at 0000:7c00
+ *
+ * @ret rc		Return status code
+ */
+int pxe_start_nbp ( void ) {
+	int discard_b, discard_c;
+	uint16_t rc;
+
+	/* Far call to PXE NBP */
+	__asm__ __volatile__ ( REAL_CODE ( "pushw %%cx\n\t"
+					   "pushw %%ax\n\t"
+					   "movw %%cx, %%es\n\t"
+					   "lcall $0, $0x7c00\n\t"
+					   "addw $4, %%sp\n\t" )
+			       : "=a" ( rc ), "=b" ( discard_b ),
+			         "=c" ( discard_c )
+			       :  "a" ( & __from_text16 ( ppxe ) ),
+			          "b" ( & __from_text16 ( pxenv ) ),
+			          "c" ( rm_cs )
+			       : "edx", "esi", "edi", "ebp", "memory" );
+
+	return rc;
+}

src/interface/pxe/pxe_preboot.c

 #include <gpxe/dhcp.h>
 #include <dhcp_basemem.h>
 #include "pxe.h"
-#include "pxe_callbacks.h"
+#include "pxe_call.h"
 
 /**
  * UNLOAD BASE CODE STACK
  */
 PXENV_EXIT_t pxenv_restart_tftp ( struct s_PXENV_TFTP_READ_FILE
 				  *restart_tftp ) {
-	DBG ( "PXENV_RESTART_TFTP" );
+	PXENV_EXIT_t tftp_exit;
+
+	DBG ( "PXENV_RESTART_TFTP " );
 
-#if 0
 	/* Words cannot describe the complete mismatch between the PXE
 	 * specification and any possible version of reality...
 	 */
-	restart_tftp->Buffer = PXE_LOAD_ADDRESS; /* Fixed by spec, apparently */
-	restart_tftp->BufferSize = get_free_base_memory() - PXE_LOAD_ADDRESS; /* Near enough */
-	DBG ( "(" );
-	tftp_exit = pxe_api_call ( PXENV_TFTP_READ_FILE, (union u_PXENV_ANY*)restart_tftp );
-	DBG ( ")" );
-	if ( tftp_exit != PXENV_EXIT_SUCCESS ) return tftp_exit;
+	restart_tftp->Buffer = PXE_LOAD_PHYS; /* Fixed by spec, apparently */
+	restart_tftp->BufferSize = ( 0xa0000 - PXE_LOAD_PHYS ); /* Near enough */
+	tftp_exit = pxenv_tftp_read_file ( restart_tftp );
+	if ( tftp_exit != PXENV_EXIT_SUCCESS )
+		return tftp_exit;
 
 	/* Fire up the new NBP */
-	restart_tftp->Status = xstartpxe();
-#endif
+	restart_tftp->Status = pxe_start_nbp();
 
 	/* Not sure what "SUCCESS" actually means, since we can only
 	 * return if the new NBP failed to boot...