Checking in obsolete but working memory-scanning code just for the record

diff --git a/src/arch/i386/drivers/bus/pxebus.c b/src/arch/i386/drivers/bus/pxebus.c
index 7ad3b6a..4876fa2 100644 (file)
--- a/src/arch/i386/drivers/bus/pxebus.c
+++ b/src/arch/i386/drivers/bus/pxebus.c
@@ -1,3 +1,5 @@
+#if 0
+

 /*
  * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
  *
 /*
  * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
  *


@@ -22,7 +24,10 @@
 #include <assert.h>
 #include <pxe.h>
 #include <realmode.h>
 #include <assert.h>
 #include <pxe.h>
 #include <realmode.h>

+#include <bios.h>
+#include <pnpbios.h>

 #include <gpxe/device.h>
 #include <gpxe/device.h>

+#include <gpxe/pci.h>

 
 /** @file
  *
 
 /** @file
  *


@@ -30,84 +35,6 @@
  *
  */
 
  *
  */
 

-/**
- * UNDI parameter block
- *
- * Used as the paramter block for all UNDI API calls.  Resides in base
- * memory.
- */
-static union u_PXENV_ANY __data16 ( pxe_params );
-#define pxe_params __use_data16 ( pxe_params )
-
-/** UNDI entry point */
-static SEGOFF16_t __data16 ( pxe_entry_point );
-#define pxe_entry_point __use_data16 ( pxe_entry_point )
-
-/**
- * Issue PXE API call
- *
- * @v pxe              PXE device
- * @v function         API call number
- * @v params           PXE parameter block
- * @v params_len       Length of PXE parameter block
- * @ret rc             Return status code
- */
-int pxe_call ( struct pxe_device *pxe, unsigned int function,
-              void *params, size_t params_len ) {
-       union u_PXENV_ANY *pxenv_any = params;
-       PXENV_EXIT_t exit;
-       int discard_b, discard_D;
-       int rc;
-
-       /* Copy parameter block and entry point */
-       assert ( params_len <= sizeof ( pxe_params ) );
-       memcpy ( &pxe_params, params, params_len );
-       pxe_entry_point = pxe->entry;
-
-       /* Call real-mode entry point.  This calling convention will
-        * work with both the !PXE and the PXENV+ entry points.
-        */
-       __asm__ __volatile__ ( REAL_CODE ( "pushw %%es\n\t"
-                                          "pushw %%di\n\t"
-                                          "pushw %%bx\n\t"
-                                          "lcall *%c3\n\t"
-                                          "addw $6, %%sp\n\t" )
-                              : "=a" ( exit ), "=b" ( discard_b ),
-                                "=D" ( discard_D )
-                              : "p" ( & __from_data16 ( pxe_entry_point ) ),
-                                "b" ( function ),
-                                "D" ( & __from_data16 ( pxe_params ) ) );
-
-       /* UNDI API calls may rudely change the status of A20 and not
-        * bother to restore it afterwards.  Intel is known to be
-        * guilty of this.
-        *
-        * Note that we will return to this point even if A20 gets
-        * screwed up by the UNDI driver, because Etherboot always
-        * resides in an even megabyte of RAM.
-        */     
-       gateA20_set();
-
-       /* Copy parameter block back */
-       memcpy ( params, &pxe_params, params_len );
-
-       /* Determine return status code based on PXENV_EXIT and
-        * PXENV_STATUS
-        */
-       if ( exit == PXENV_EXIT_SUCCESS ) {
-               rc = 0;
-       } else {
-               rc = -pxenv_any->Status;
-               /* Paranoia; don't return success for the combination
-                * of PXENV_EXIT_FAILURE but PXENV_STATUS_SUCCESS
-                */
-               if ( rc == 0 )
-                       rc = -EIO;
-       }
-
-       return rc;
-}
-

 /**
  * Byte checksum
  *
 /**
  * Byte checksum
  *


@@ -125,82 +52,6 @@ static uint8_t checksum ( void *data, size_t len ) {
        return sum;
 }
 
        return sum;
 }
 

-/**
- * Get PXE device information for an instantiated device
- *
- * @v pxe              PXE device
- * @ret rc             Return status code
- */
-static int pxedev_get_instance_info ( struct pxe_device *pxe ) {
-       struct s_PXENV pxenv;
-       struct s_PXE ppxe;
-       struct s_PXENV_UNDI_GET_INFORMATION undi_info;
-       int rc;
-
-       /* Determine entry point from PXENV+ structure */
-       DBGC ( pxe, "PXE %p has PXENV+ structure at %04x:%04x\n", pxe,
-             pxe->pxenv.segment, pxe->pxenv.offset );
-       copy_from_real ( &pxenv, pxe->pxenv.segment, pxe->pxenv.offset,
-                        sizeof ( pxenv ) );
-       if ( checksum ( &pxenv, sizeof ( pxenv ) ) != 0 ) {
-               DBGC ( pxe, "PXE %p bad PXENV+ checksum\n", pxe );
-               return -EINVAL;
-       }
-       pxe->entry = pxenv.RMEntry;
-
-       /* If API version is 2.1 or greater, use the !PXE structure instead */
-       if ( pxenv.Version >= 0x0201 ) {
-               pxe->ppxe = pxenv.PXEPtr;
-               DBGC ( pxe, "PXE %p has !PXE structure at %04x:%04x\n", pxe,
-                      pxe->ppxe.segment, pxe->ppxe.offset );
-               copy_from_real ( &ppxe, pxe->ppxe.segment, pxe->ppxe.offset,
-                                sizeof ( ppxe ) );
-               if ( checksum ( &pxenv, sizeof ( pxenv ) ) != 0 ) {
-                       DBGC ( pxe, "PXE %p bad !PXE checksum\n", pxe );
-                       return -EINVAL;
-               }
-               pxe->entry = ppxe.EntryPointSP;
-       }
-
-       DBGC ( pxe, "PXE %p using entry point at %04x:%04x\n", pxe,
-              pxe->entry.segment, pxe->entry.offset );
-
-       /* Get device information */
-       memset ( &undi_info, 0, sizeof ( undi_info ) );
-       if ( ( rc = pxe_call ( pxe, PXENV_UNDI_GET_INFORMATION, &undi_info,
-                              sizeof ( undi_info ) ) ) != 0 ) {
-               DBGC ( pxe, "PXE %p could not retrieve UNDI information: %s\n",
-                      pxe, strerror ( rc ) );
-               return rc;
-       }
-       memcpy ( pxe->hwaddr, undi_info.PermNodeAddress,
-                sizeof ( pxe->hwaddr ) );
-       pxe->irq = undi_info.IntNumber;
-       pxe->rom_segment = undi_info.ROMAddress;
-
-       return 0;
-}
-
-/**
- * Register PXE device
- *
- * @v pxe              PXE device
- * @ret rc             Return status code
- */
-static int register_pxedev ( struct pxe_device *pxe ) {
-       int rc;
-
-       DBGC ( pxe, "PXE %p registering\n", pxe );
-
-       /* Register as an UNDI driver */
-       if ( ( rc = undi_probe ( pxe ) ) != 0 )
-               return rc;
-
-       /* Add to device hierarchy and return */
-       list_add ( &pxe->dev.siblings, &pxe->dev.parent->children );
-       return 0;
-}
-

 /**
  * Unregister a PXE device
  *
 /**
  * Unregister a PXE device
  *


@@ -224,47 +75,74 @@ static void pxebus_remove ( struct root_device *rootdev );
  * find.
  */
 static int pxebus_probe ( struct root_device *rootdev ) {
  * find.
  */
 static int pxebus_probe ( struct root_device *rootdev ) {

-       struct pxe_device *pxe;
-       uint16_t signature;
-       uint16_t pxenv_segment;
-       uint16_t pxenv_offset;
+       struct pxe_device *pxe = NULL;
+       struct s_PXENV pxenv;
+       struct s_PXE ppxe;
+       uint16_t fbms;
+       unsigned int segment;
+       unsigned int undi_cs;

        int rc;
 
        int rc;
 

-       /* PXE installation check */
-       __asm__ __volatile__ ( REAL_CODE ( "stc\n\t"
-                                          "int $0x1a\n\t"
-                                          "jnc 1f\n\t"
-                                          "xorw %%ax, %%ax\n\t"
-                                          "\n1:\n\t"
-                                          "movw %%es, %%dx\n\t" )
-                              : "=a" ( signature ), "=b" ( pxenv_offset ),
-                                "=d" ( pxenv_segment )
-                              : "a" ( 0x5650 ) );
-       if ( signature != 0x564e ) {
-               DBG ( "No pixies found\n" );
-               return 0;
-       }
-
-       /* Allocate PXE device structure */
-       pxe = malloc ( sizeof ( *pxe ) );
-       if ( ! pxe ) {
-               rc = -ENOMEM;
-               goto err;
-       }
-       memset ( pxe, 0, sizeof ( *pxe ) );
+       /* Scan through allocated base memory for PXENV+ structure */
+       get_real ( fbms, BDA_SEG, BDA_FBMS );
+       for ( segment = ( fbms << 6 ) ; segment < 0xa000 ; segment++ ) {

 
 

-       /* Populate PXE device structure */
-       pxe->pxenv.segment = pxenv_segment;
-       pxe->pxenv.offset = pxenv_offset;
-       INIT_LIST_HEAD ( &pxe->dev.children );
-       pxe->dev.parent = &rootdev->dev;
-       if ( ( rc = pxedev_get_instance_info ( pxe ) ) != 0 )
-               goto err;
+               /* Verify PXENV+ signature and checksum */
+               copy_from_real ( &pxenv, segment, 0, sizeof ( pxenv ) );
+               if ( memcmp ( pxenv.Signature, "PXENV+", 6 ) != 0 )
+                       continue;
+               DBG ( "Found PXENV+ signature at %04x0\n", segment );
+               if ( checksum ( &pxenv, sizeof ( pxenv ) ) != 0 ) {
+                       DBG ( "...bad checksum\n" );
+                       continue;
+               }

 
 

-       /* Register PXE device */
-       if ( ( rc = register_pxedev ( pxe ) ) != 0 )
-               goto err;
+               /* Allocate PXE device structure */
+               pxe = malloc ( sizeof ( *pxe ) );
+               if ( ! pxe ) {
+                       rc = -ENOMEM;
+                       goto err;
+               }
+               memset ( pxe, 0, sizeof ( *pxe ) );
+
+               /* Add to device hierarchy */
+               pxe->dev.parent = &rootdev->dev;
+               INIT_LIST_HEAD ( &pxe->dev.children );
+               list_add ( &pxe->dev.siblings, &rootdev->dev.children );
+
+               /* Populate PXE device structure */
+               undi_cs = pxenv.UNDICodeSeg;
+               pxe->pxenv.segment = undi_cs;
+               pxe->pxenv.offset = ( ( segment - undi_cs ) << 4 );
+               DBGC ( pxe, "PXE %p has PXENV+ structure at %04x:%04x\n",
+                      pxe, pxe->pxenv.segment, pxe->pxenv.offset );
+               pxe->entry = pxenv.RMEntry;
+               if ( pxenv.Version >= 0x0201 ) {
+                       pxe->ppxe = pxenv.PXEPtr;
+                       copy_from_real ( &ppxe, pxe->ppxe.segment,
+                                        pxe->ppxe.offset, sizeof ( ppxe ) );
+                       if ( ( memcmp ( ppxe.Signature, "!PXE", 4 ) == 0 ) &&
+                            ( checksum ( &ppxe, sizeof ( ppxe ) ) == 0 ) ) {
+                               DBGC ( pxe, "PXE %p has !PXE structure at "
+                                      "%04x:%04x\n", pxe,
+                                      pxe->ppxe.segment, pxe->ppxe.offset );
+                               pxe->entry = ppxe.EntryPointSP;
+                       }
+               }
+               DBGC ( pxe, "PXE %p using entry point at %04x:%04x\n", pxe,
+                      pxe->entry.segment, pxe->entry.offset );
+
+               /* Register PXE device */
+               if ( undi_probe ( pxe ) == 0 ) {
+                       /* Device registered; drop reference */
+                       pxe = NULL;
+               } else {
+                       /* Not registered; re-use struct pxe_device */
+                       list_del ( &pxe->dev.siblings );
+               }
+       }

 
 

+       free ( pxe );

        return 0;
 
  err:
        return 0;
 
  err:


@@ -299,7 +177,6 @@ static struct root_driver pxe_root_driver = {
 struct root_device pxe_root_device __root_device = {
        .name = "PXE",
        .driver = &pxe_root_driver,
 struct root_device pxe_root_device __root_device = {
        .name = "PXE",
        .driver = &pxe_root_driver,

-       .dev = {
-               .children = LIST_HEAD_INIT ( pxe_root_device.dev.children ),
-       },

 };
 };

+
+#endif