Changeset d681c17 in mainline for kernel/arch/sparc64/src/start.S

Timestamp:

2006-09-05T14:52:11Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

5035eeb7

Parents:

2def788

Message:

sparc64 work.

• the syscall wrapper needs to use the "memory" clobber specifier to prevent over-optimization.
• on sparc64, the user address space spans the whole 64-bit space and therefore the macro USER_ADDRESS_SPACE_SIZE_ARCH, as it was defined, overflows to 0
• stop using USER_ADDRESS_SPACE_SIZE_ARCH and define MAX_HEAP_SIZE instead
• in our situation when kernel and user address spaces are separate, the G (global) bit cannot be used (there is no point in it anymore)
• add the DEBUG() macro to stdio.h; DEBUG() uses SYS_IO and is a good debugging tool for getting early userspace to work

File:

• kernel/arch/sparc64/src/start.S (modified) (1 diff)

kernel/arch/sparc64/src/start.S

@@ -126 +126 @@
         
         ! write DTLB data and install the kernel mapping
-        SET_TLB_DATA(g1, g2, TTE_G)
+        SET_TLB_DATA(g1, g2, 0)                 ! use non-global mapping
+        stxa %g1, [%g0] ASI_DTLB_DATA_IN_REG            
+        membar #Sync
+
+        /*
+         * Because we cannot use global mappings (because we want to
+         * have separate 64-bit address spaces for both the kernel
+         * and the userspace), we prepare the identity mapping also in
+         * context 1. This step is required by the
+         * code installing the ITLB mapping.
+         */
+        ! write DTLB tag of context 1 (i.e. MEM_CONTEXT_TEMP)
+        SET_TLB_TAG(g1, MEM_CONTEXT_TEMP)
+        stxa %g1, [VA_DMMU_TAG_ACCESS] %asi                     
+        membar #Sync
+
+        ! write DTLB data and install the kernel mapping in context 1
+        SET_TLB_DATA(g1, g2, 0)                 ! use non-global mapping
         stxa %g1, [%g0] ASI_DTLB_DATA_IN_REG            
         membar #Sync