ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

target/hppa: Implement PSW_X 

Use PAGE_WRITE_INV to temporarily enable write permission
on for a given page, driven by PSW_X being set.

Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2024-04-16 17:39:25 -07:00
parent 5ae8adbb01
commit d8bc138125
1 changed files with 27 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
target/hppa/mem_helper.c
View File

@ -296,30 +296,38 @@ int hppa_get_physical_address(CPUHPPAState *env, vaddr addr, int mmu_idx,
goto egress; goto egress;
} }
/* In reverse priority order, check for conditions which raise faults. /*
As we go, remove PROT bits that cover the condition we want to check. * In priority order, check for conditions which raise faults.
In this way, the resulting PROT will force a re-check of the * Remove PROT bits that cover the condition we want to check,
architectural TLB entry for the next access. */ * so that the resulting PROT will force a re-check of the
if (unlikely(!ent->d)) { * architectural TLB entry for the next access.
if (type & PAGE_WRITE) { */
/* The D bit is not set -- TLB Dirty Bit Fault. */
ret = EXCP_TLB_DIRTY;
}
prot &= PAGE_READ | PAGE_EXEC;
}
if (unlikely(ent->b)) {
if (type & PAGE_WRITE) {
/* The B bit is set -- Data Memory Break Fault. */
ret = EXCP_DMB;
}
prot &= PAGE_READ | PAGE_EXEC;
}
if (unlikely(ent->t)) { if (unlikely(ent->t)) {
prot &= PAGE_EXEC;
if (!(type & PAGE_EXEC)) { if (!(type & PAGE_EXEC)) {
/* The T bit is set -- Page Reference Fault. */ /* The T bit is set -- Page Reference Fault. */
ret = EXCP_PAGE_REF; ret = EXCP_PAGE_REF;
} }
prot &= PAGE_EXEC; } else if (!ent->d) {
prot &= PAGE_READ | PAGE_EXEC;
if (type & PAGE_WRITE) {
/* The D bit is not set -- TLB Dirty Bit Fault. */
ret = EXCP_TLB_DIRTY;
}
} else if (unlikely(ent->b)) {
prot &= PAGE_READ | PAGE_EXEC;
if (type & PAGE_WRITE) {
/*
* The B bit is set -- Data Memory Break Fault.
* Except when PSW_X is set, allow this single access to succeed.
* The write bit will be invalidated for subsequent accesses.
*/
if (env->psw_xb & PSW_X) {
prot |= PAGE_WRITE_INV;
} else {
ret = EXCP_DMB;
}
}
} }
egress: egress: