Partial implementation of UNDI loader caller.

src/arch/i386/drivers/bus/pxedrv.c

 #include <string.h>
 #include <pxe.h>
 #include <realmode.h>
+#include <bios.h>
 
 /** @file
  *
 	}
 
 	/* Fill in PXE driver loader fields */
-	pxedrv->loader.segment = pxedrv->rom_segment;
-	pxedrv->loader.offset = undiloader;
+	pxedrv->loader_entry.segment = pxedrv->rom_segment;
+	pxedrv->loader_entry.offset = undiloader;
 	pxedrv->code_size = undi_rom_id.CodeSize;
 	pxedrv->data_size = undi_rom_id.DataSize;
 
 	DBGC ( pxedrv, "PXEDRV %p has UNDI loader at %04x:%04x "
-	       "(code %04x data %04x)\n", pxedrv, pxedrv->loader.segment,
-	       pxedrv->loader.offset, pxedrv->code_size, pxedrv->data_size );
+	       "(code %04x data %04x)\n", pxedrv,
+	       pxedrv->loader_entry.segment, pxedrv->loader_entry.offset,
+	       pxedrv->code_size, pxedrv->data_size );
 	return 0;
 }
 
 	      vendor_id, device_id, rombase );
 	return NULL;
 }
+
+/** Parameter block for calling UNDI loader */
+static struct s_UNDI_LOADER __data16 ( undi_loader );
+#define undi_loader __use_data16 ( undi_loader )
+
+/** UNDI loader entry point */
+static SEGOFF16_t __data16 ( undi_loader_entry );
+#define undi_loader_entry __use_data16 ( undi_loader_entry )
+
+/**
+ * Call UNDI loader to create a pixie
+ *
+ * @v pxedrv		PXE driver
+ * @v pxe		PXE device to be created
+ * @v pci_busdevfn	PCI bus:dev.fn (PCI devices only), or 0
+ * @v isapnp_csn	ISAPnP Card Select Number, or -1U
+ * @v isapnp_read_port	ISAPnP read port, or -1U
+ * @ret rc		Return status code
+ */
+static int pxedrv_load ( struct pxe_driver *pxedrv, struct pxe_device *pxe,
+			 unsigned int pci_busdevfn, unsigned int isapnp_csn,
+			 unsigned int isapnp_read_port ) {
+	int discard;
+	uint16_t exit;
+	uint16_t fbms;
+	unsigned int fbms_seg;
+	int rc;
+
+	memset ( &undi_loader, 0, sizeof ( undi_loader ) );
+	undi_loader.AX = pci_busdevfn;
+	undi_loader.BX = isapnp_csn;
+	undi_loader.DX = isapnp_read_port;
+
+	/* Allocate base memory for PXE stack */
+	get_real ( fbms, BDA_SEG, BDA_FBMS );
+	fbms_seg = ( fbms << 6 );
+	fbms_seg -= ( ( pxedrv->data_size + 0x0f ) >> 4 );
+	undi_loader.UNDI_DS = fbms_seg;
+	fbms_seg -= ( ( pxedrv->code_size + 0x0f ) >> 4 );
+	undi_loader.UNDI_CS = fbms_seg;
+	DBGC ( pxedrv, "PXEDRV %p loading to CS %04x and DS %04x\n", pxedrv,
+	       undi_loader.UNDI_CS, undi_loader.UNDI_DS );
+
+	/* Call loader */
+	undi_loader_entry = pxedrv->loader_entry;
+	__asm__ __volatile__ ( REAL_CODE ( "pushw %%ds\n\t"
+					   "pushw %w0\n\t"
+					   "lcall *%c3\n\t"
+					   "addw $4, %%sp\n\t" )
+			       : "=a" ( exit ), "=r" ( discard )
+			       : "0" ( & __from_data16 ( undi_loader ) ),
+			         "p" ( & __from_data16 ( undi_loader_entry )));
+	if ( exit != PXENV_EXIT_SUCCESS ) {
+		rc = -undi_loader.Status;
+		if ( rc == 0 ) /* Paranoia */
+			rc = -EIO;
+		DBGC ( pxedrv, "PXEDRV %p loader failed: %s\n",
+		       strerror ( rc ) );
+		return rc;
+	}
+
+	/* Update free base memory counter */
+	fbms = ( fbms_seg >> 6 );
+	put_real ( fbms, BDA_SEG, BDA_FBMS );
+
+	/* Record location of pixie in PXE device structure */
+	pxe->pxenv = undi_loader.PXENVptr;
+	pxe->ppxe = undi_loader.PXEptr;
+	return 0;
+}
+
+/**
+ * Call UNDI loader to create a pixie
+ *
+ * @v pxedrv		PXE driver
+ * @v pxe		PXE device to be created
+ * @v pci_busdevfn	PCI bus:dev.fn
+ * @ret rc		Return status code
+ */
+int pxedrv_load_pci ( struct pxe_driver *pxedrv, struct pxe_device *pxe,
+		      unsigned int bus, unsigned int devfn ) {
+	return pxedrv_load ( pxedrv, pxe, ( ( bus << 8 ) | devfn ), -1U, -1U );
+}

src/arch/i386/include/bios.h

 #define BIOS_H
 
 #define BDA_SEG 0x0040
+#define BDA_FBMS 0x0013
 #define BDA_NUM_DRIVES 0x0075
 
 extern unsigned long currticks ( void );

src/include/pxe.h

 	/** ROM segment address */
 	unsigned int rom_segment;
 	/** UNDI loader entry point */
-	SEGOFF16_t loader;
+	SEGOFF16_t loader_entry;
 	/** Code segment size */
 	size_t code_size;
 	/** Data segment size */

src/include/pxe_api.h

  * @{
  */
 
-/** The UNDI ROM ID structure */
-struct s_UNDI_ROM_ID {
-	/** Signature
-	 *
-	 * Contains the bytes 'U', 'N', 'D', 'I'.
-	 */
-	UINT32_t Signature;
-	UINT8_t StructLength;		/**< Length of this structure */
-	/** Checksum
-	 *
-	 * The byte checksum of this structure (using the length in
-	 * #StructLength) must be zero.
-	 */
-	UINT8_t StructCksum;
-	/** Revision of this structure
-	 *
-	 * For PXE version 2.1, this field must be zero.
-	 */
-	UINT8_t StructRev;
-	/** UNDI revision
-	 *
-	 * UNDI revision, least significant byte first.  For UNDI
-	 * version 2.1.0, this field will contain { 0x00, 0x01, 0x02 }.
-	 */
-	UINT8_t UNDIRev[3];
-	/** UNDI loader routine entry point
-	 *
-	 * This is the entry point for calling undi_loader().
-	 */
-	UINT16_t UNDILoader;
-	/** Minimum required stack segment size */
-	UINT16_t StackSize;
-	/** Minimum required data segment size */
-	UINT16_t DataSize;
-	/** Minimum required code segment size */
-	UINT16_t CodeSize;
-} PACKED;
-
-typedef struct s_UNDI_ROM_ID UNDI_ROM_ID_t;
-
 /** Parameter block for undi_loader() */
 struct s_UNDI_LOADER {
-	/** struct s_UNDI_LOADER starts with a struct s_PXENV_START_UNDI */
-	union undi_loader_start_undi {
-		PXENV_STATUS_t Status;		/**< PXE status code */
-		/** Parameters to pass to pxenv_start_undi() */
-		struct s_PXENV_START_UNDI start_undi;
-	} u;
+	/** PXE status code */
+	PXENV_STATUS_t Status;
+	/** %ax register as for PXENV_START_UNDI */
+	UINT16_t AX;
+	/** %bx register as for PXENV_START_UNDI */
+	UINT16_t BX;
+	/** %dx register as for PXENV_START_UNDI */
+	UINT16_t DX;
+	/** %di register as for PXENV_START_UNDI */
+	OFF16_t DI;
+	/** %es register as for PXENV_START_UNDI */
+	SEGSEL_t ES;
 	/** UNDI data segment
 	 *
 	 * @note The PXE specification defines the type of this field
 	 * equivalent anyway; for other architectures #SEGSEL_t makes
 	 * more sense.
 	 */
-	SEGSEL_t	undi_ds;
+	SEGSEL_t UNDI_DS;
 	/** UNDI code segment
 	 *
 	 * @note The PXE specification defines the type of this field
 	 * equivalent anyway; for other architectures #SEGSEL_t makes
 	 * more sense.
 	 */
-	SEGSEL_t	undi_cs;
+	SEGSEL_t UNDI_CS;
 	/** Address of the !PXE structure (a struct s_PXE) */
-	SEGOFF16_t	pxe_ptr;
+	SEGOFF16_t PXEptr;
 	/** Address of the PXENV+ structure (a struct s_PXENV) */
-	SEGOFF16_t	pxenv_ptr;
+	SEGOFF16_t PXENVptr;
 } PACKED;
 
 typedef struct s_UNDI_LOADER UNDI_LOADER_t;