[bios] Allow rtc_entropy.c to be compiled for x86_64

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

diff --git a/src/arch/i386/interface/pcbios/rtc_entropy.c b/src/arch/i386/interface/pcbios/rtc_entropy.c
index 89b7975818306b1536e8b3b67bf96afbafcef759..6e7ac833e3f36f2aaee3ffcdced77c1268952dea 100644 (file)
--- a/src/arch/i386/interface/pcbios/rtc_entropy.c
+++ b/src/arch/i386/interface/pcbios/rtc_entropy.c
@@ -36,10 +36,6 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #include <rtc.h>
 #include <ipxe/entropy.h>
 
-/** RTC "interrupt triggered" flag */
-static uint8_t __text16 ( rtc_flag );
-#define rtc_flag __use_text16 ( rtc_flag )
-
 /** RTC interrupt handler */
 extern void rtc_isr ( void );
 
@@ -58,23 +54,24 @@ static void rtc_hook_isr ( void ) {
                              /* Preserve registers */
                              "pushw %%ax\n\t"
                              /* Set "interrupt triggered" flag */
-                             "cs movb $0x01, %c0\n\t"
+                             "movb $0x01, %%cs:rtc_flag\n\t"
                              /* Read RTC status register C to
                               * acknowledge interrupt
                               */
-                             "movb %3, %%al\n\t"
-                             "outb %%al, %1\n\t"
-                             "inb %2\n\t"
+                             "movb %2, %%al\n\t"
+                             "outb %%al, %0\n\t"
+                             "inb %1\n\t"
                              /* Send EOI */
                              "movb $0x20, %%al\n\t"
                              "outb %%al, $0xa0\n\t"
                              "outb %%al, $0x20\n\t"
                              /* Restore registers and return */
                              "popw %%ax\n\t"
-                             "iret\n\t" )
+                             "iret\n\t"
+                             "\nrtc_flag:\n\t"
+                             ".byte 0\n\t" )
                :
-               : "p" ( __from_text16 ( &rtc_flag ) ),
-                 "i" ( CMOS_ADDRESS ), "i" ( CMOS_DATA ),
+               : "i" ( CMOS_ADDRESS ), "i" ( CMOS_DATA ),
                  "i" ( RTC_STATUS_C ) );
 
        hook_bios_interrupt ( RTC_INT, ( intptr_t ) rtc_isr, &rtc_old_handler );
@@ -167,9 +164,9 @@ uint8_t rtc_sample ( void ) {
                REAL_CODE ( /* Enable interrupts */
                            "sti\n\t"
                            /* Wait for RTC interrupt */
-                           "cs movb %b2, %c4\n\t"
+                           "movb %b2, %%cs:rtc_flag\n\t"
                            "\n1:\n\t"
-                           "cs xchgb %b2, %c4\n\t" /* Serialize */
+                           "xchgb %b2, %%cs:rtc_flag\n\t" /* Serialize */
                            "testb %b2, %b2\n\t"
                            "jz 1b\n\t"
                            /* Read "before" TSC */
@@ -178,9 +175,9 @@ uint8_t rtc_sample ( void ) {
                            "pushl %0\n\t"
                            /* Wait for another RTC interrupt */
                            "xorb %b2, %b2\n\t"
-                           "cs movb %b2, %c4\n\t"
+                           "movb %b2, %%cs:rtc_flag\n\t"
                            "\n1:\n\t"
-                           "cs xchgb %b2, %c4\n\t" /* Serialize */
+                           "xchgb %b2, %%cs:rtc_flag\n\t" /* Serialize */
                            "testb %b2, %b2\n\t"
                            "jz 1b\n\t"
                            /* Read "after" TSC */
@@ -191,7 +188,7 @@ uint8_t rtc_sample ( void ) {
                            "cli\n\t"
                            )
                : "=a" ( after ), "=d" ( before ), "=q" ( temp )
-               : "2" ( 0 ), "p" ( __from_text16 ( &rtc_flag ) ) );
+               : "2" ( 0 ) );
 
        return ( after - before );
 }