Add (untested) UNDI loader C-level implementation.

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

 	ix86->regs.ax = ret;
 }
 
+/**
+ * Dispatch PXE loader call
+ *
+ * @v es:di		Address of PXE parameter block
+ * @ret ax		PXE exit code
+ */
+void pxe_loader_call ( struct i386_all_regs *ix86 ) {
+	userptr_t uparams = real_to_user ( ix86->segs.es, ix86->regs.di );
+	struct s_UNDI_LOADER params;
+	PXENV_EXIT_t ret;
+
+	/* Copy parameter block from caller */
+	copy_from_user ( &params, uparams, 0, sizeof ( params ) );
+
+	/* Set default status in case child routine fails to do so */
+	params.Status = PXENV_STATUS_FAILURE;
+
+	/* Call UNDI loader */
+	ret = undi_loader ( &params );
+
+	/* Copy modified parameter block back to caller and return */
+	copy_to_user ( uparams, 0, &params, sizeof ( params ) );
+	ix86->regs.ax = ret;
+}
+
 /**
  * Hook INT 1A for PXE
  *

src/interface/pxe/pxe_loader.c

-/** @file
- *
- * PXE UNDI loader
- *
- */
-
 /*
- * Copyright (C) 2004 Michael Brown <mbrown@fensystems.co.uk>.
+ * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#warning "Currently broken"
-#if 0
+#include <gpxe/init.h>
 #include "pxe.h"
+#include "pxe_call.h"
 
-/* PXENV_UNDI_LOADER
+/** @file
+ *
+ * PXE UNDI loader
  *
- * Status: working
+ */
+
+/* PXENV_UNDI_LOADER
  *
- * NOTE: This is not a genuine PXE API call; the loader has a separate
- * entry point.  However, to simplify the mapping of the PXE API to
- * the internal Etherboot API, both are directed through the same
- * interface.
  */
 PXENV_EXIT_t undi_loader ( struct s_UNDI_LOADER *undi_loader ) {
-	uint32_t loader_phys = virt_to_phys ( undi_loader );
-
-	DBG ( "PXENV_UNDI_LOADER" );
-	
-	/* Set UNDI DS as our real-mode stack */
-	use_undi_ds_for_rm_stack ( undi_loader->undi_ds );
-
-	/* FIXME: These lines are borrowed from main.c.  There should
-	 * probably be a single initialise() function that does all
-	 * this, but it's currently split interestingly between main()
-	 * and main_loop()...
-	 */
-
-
-	/* CHECKME: Our init functions have probably already been
-	   called by the ROM prefix's call to setup(), haven't
-	   they? */
-
 
+	DBG ( "[PXENV_UNDI_LOADER]" );
 
-	/* We have relocated; the loader pointer is now invalid */
-	undi_loader = phys_to_virt ( loader_phys );
+	/* Perform one-time initialisation (e.g. heap) */
+	initialise();
 
-	/* Install PXE stack to area specified by NBP */
-	install_pxe_stack ( VIRTUAL ( undi_loader->undi_cs, 0 ) );
-	
-	/* Call pxenv_start_undi to set parameters.  Why the hell PXE
-	 * requires these parameters to be provided twice is beyond
-	 * the wit of any sane man.  Don't worry if it fails; the NBP
-	 * should call PXENV_START_UNDI separately anyway.
-	 */
-	pxenv_start_undi ( &undi_loader->u.start_undi );
-	/* Unhook stack; the loader is not meant to hook int 1a etc,
-	 * but the call the pxenv_start_undi will cause it to happen.
-	 */
+	/* Set up PXE data structures */
+	pxe_init_structures();
 
-	/* FIXME: can't use ENSURE_CAN_UNLOAD() thanks to newer gcc's
-	 * barfing on unnamed struct/unions. */
-	/*	ENSURE_CAN_UNLOAD ( undi_loader ); */
+	/* Fill in UNDI loader structure */
+	undi_loader->PXEptr.segment = rm_ds;
+	undi_loader->PXEptr.offset =
+		( ( unsigned ) & __from_text16 ( ppxe ) );
+	undi_loader->PXENVptr.segment = rm_ds;
+	undi_loader->PXENVptr.offset =
+		( ( unsigned ) & __from_text16 ( pxenv ) );
 
-	/* Fill in addresses of !PXE and PXENV+ structures */
-	PTR_TO_SEGOFF16 ( &pxe_stack->pxe, undi_loader->pxe_ptr );
-	PTR_TO_SEGOFF16 ( &pxe_stack->pxenv, undi_loader->pxenv_ptr );
-	
-	undi_loader->u.Status = PXENV_STATUS_SUCCESS;
+	undi_loader->Status = PXENV_STATUS_SUCCESS;
 	return PXENV_EXIT_SUCCESS;
 }
-#endif

src/interface/pxe/pxe_preboot.c

  */
 static char *pxe_ris_filename = NULL;
 
+/* Avoid dragging in isapnp.o unnecessarily */
+uint16_t isapnp_read_port;
+
 /**
  * UNLOAD BASE CODE STACK
  *
  * Status: working
  */
 PXENV_EXIT_t pxenv_start_undi ( struct s_PXENV_START_UNDI *start_undi ) {
-	unsigned int isapnp_read_port;
-	unsigned int isapnp_csn;
-	unsigned int pci_busdevfn;
 	unsigned int bus_type;
 	unsigned int location;
 	struct net_device *netdev;
 	DBG ( "PXENV_START_UNDI %04x:%04x:%04x",
 	      start_undi->AX, start_undi->BX, start_undi->DX );
 
-	/* Probe for devices, etc. */
-	startup();
-
-	/* Determine bus type and location */
-	isapnp_read_port = start_undi->DX;
-	isapnp_csn = start_undi->BX;
-	pci_busdevfn = start_undi->AX;
-
-	/* Use a heuristic to decide whether we are PCI or ISAPnP */
-	if ( ( isapnp_read_port >= ISAPNP_READ_PORT_MIN ) &&
-	     ( isapnp_read_port <= ISAPNP_READ_PORT_MAX ) &&
-	     ( isapnp_csn >= ISAPNP_CSN_MIN ) &&
-	     ( isapnp_csn <= ISAPNP_CSN_MAX ) ) {
+	/* Determine bus type and location.  Use a heuristic to decide
+	 * whether we are PCI or ISAPnP
+	 */
+	if ( ( start_undi->DX >= ISAPNP_READ_PORT_MIN ) &&
+	     ( start_undi->DX <= ISAPNP_READ_PORT_MAX ) &&
+	     ( start_undi->BX >= ISAPNP_CSN_MIN ) &&
+	     ( start_undi->BX <= ISAPNP_CSN_MAX ) ) {
 		bus_type = BUS_TYPE_ISAPNP;
-		location = isapnp_csn;
+		location = start_undi->BX;
+		/* Record ISAPnP read port for use by isapnp.c */
+		isapnp_read_port = start_undi->DX;
 	} else {
 		bus_type = BUS_TYPE_PCI;
-		location = pci_busdevfn;
+		location = start_undi->AX;
 	}
 
+	/* Probe for devices, etc. */
+	startup();
+
 	/* Look for a matching net device */
 	netdev = find_netdev_by_location ( bus_type, location );
 	if ( ! netdev ) {