add htif section in linker script, with ALIGNs to prevent MMIO and data from being placed on same page (#32)

10 years ago · f73dee6f2c
3 changed files with 22 additions and 2 deletions
--- a/bbl/bbl.lds
+++ b/bbl/bbl.lds
@ -40,6 +40,16 @@ SECTIONS
  PROVIDE( etext = . );
  _etext = .;

+  /*--------------------------------------------------------------------*/
+  /* HTIF, isolated onto separate page                                  */
+  /*--------------------------------------------------------------------*/
+  . = ALIGN(0x1000);
+  htif :
+  {
+    *(htif)
+  }
+  . = ALIGN(0x1000);
+
  /*--------------------------------------------------------------------*/
  /* Initialized data segment                                           */
  /*--------------------------------------------------------------------*/
--- a/machine/mtrap.c
+++ b/machine/mtrap.c
@ -7,8 +7,8 @@
 #include <stdarg.h>
 #include <stdio.h>

-volatile uint64_t tohost __attribute__((aligned(64)));
-volatile uint64_t fromhost __attribute__((aligned(64)));
+volatile uint64_t tohost __attribute__((aligned(64))) __attribute__((section("htif")));
+volatile uint64_t fromhost __attribute__((aligned(64))) __attribute__((section("htif")));

 void __attribute__((noreturn)) bad_trap()
 {
--- a/pk/pk.lds
+++ b/pk/pk.lds
@ -40,6 +40,16 @@ SECTIONS
  PROVIDE( etext = . );
  _etext = .;

+  /*--------------------------------------------------------------------*/
+  /* HTIF, isolated onto separate page                                  */
+  /*--------------------------------------------------------------------*/
+  . = ALIGN(0x1000);
+  htif :
+  {
+    *(htif)
+  }
+  . = ALIGN(0x1000);
+
  /*--------------------------------------------------------------------*/
  /* Initialized data segment                                           */
  /*--------------------------------------------------------------------*/