mmu-hash32: Split direct store segment handling into a helper

This further separates the unusual case handling of direct store segments
from the main translation path by moving its logic into a helper function,
with some tiny cleanups along the way.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
David Gibson 2013-03-12 00:31:25 +00:00 committed by Alexander Graf
parent 4b9605a5b1
commit 723ed73ada

View File

@ -243,6 +243,62 @@ static int ppc_hash32_get_bat(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
return ret;
}
static int ppc_hash32_direct_store(CPUPPCState *env, target_ulong sr,
target_ulong eaddr, int rwx,
hwaddr *raddr, int *prot)
{
int key = !!(msr_pr ? (sr & SR32_KP) : (sr & SR32_KS));
LOG_MMU("direct store...\n");
if ((sr & 0x1FF00000) >> 20 == 0x07f) {
/* Memory-forced I/O controller interface access */
/* If T=1 and BUID=x'07F', the 601 performs a memory access
* to SR[28-31] LA[4-31], bypassing all protection mechanisms.
*/
*raddr = ((sr & 0xF) << 28) | (eaddr & 0x0FFFFFFF);
*prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
return 0;
}
if (rwx == 2) {
/* No code fetch is allowed in direct-store areas */
return -4;
}
switch (env->access_type) {
case ACCESS_INT:
/* Integer load/store : only access allowed */
break;
case ACCESS_FLOAT:
/* Floating point load/store */
return -4;
case ACCESS_RES:
/* lwarx, ldarx or srwcx. */
return -4;
case ACCESS_CACHE:
/* dcba, dcbt, dcbtst, dcbf, dcbi, dcbst, dcbz, or icbi */
/* Should make the instruction do no-op.
* As it already do no-op, it's quite easy :-)
*/
*raddr = eaddr;
return 0;
case ACCESS_EXT:
/* eciwx or ecowx */
return -4;
default:
qemu_log("ERROR: instruction should not need "
"address translation\n");
return -4;
}
if ((rwx == 1 || key != 1) && (rwx == 0 || key != 0)) {
*raddr = eaddr;
return 2;
} else {
return -2;
}
}
static int pte_check_hash32(struct mmu_ctx_hash32 *ctx, target_ulong pte0,
target_ulong pte1, int h, int rwx)
{
@ -404,66 +460,15 @@ static int ppc_hash32_translate(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
/* 3. Look up the Segment Register */
sr = env->sr[eaddr >> 28];
/* 4. Handle direct store segments */
if (sr & SR32_T) {
return ppc_hash32_direct_store(env, sr, eaddr, rwx,
&ctx->raddr, &ctx->prot);
}
pr = msr_pr;
ctx->key = (((sr & SR32_KP) && (pr != 0)) ||
((sr & SR32_KS) && (pr == 0))) ? 1 : 0;
/* 4. Handle direct store segments */
if (sr & SR32_T) {
LOG_MMU("direct store...\n");
/* Direct-store segment : absolutely *BUGGY* for now */
/* Direct-store implies a 32-bit MMU.
* Check the Segment Register's bus unit ID (BUID).
*/
if ((sr & 0x1FF00000) >> 20 == 0x07f) {
/* Memory-forced I/O controller interface access */
/* If T=1 and BUID=x'07F', the 601 performs a memory access
* to SR[28-31] LA[4-31], bypassing all protection mechanisms.
*/
ctx->raddr = ((sr & 0xF) << 28) | (eaddr & 0x0FFFFFFF);
ctx->prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
return 0;
}
if (rwx == 2) {
/* No code fetch is allowed in direct-store areas */
return -4;
}
switch (env->access_type) {
case ACCESS_INT:
/* Integer load/store : only access allowed */
break;
case ACCESS_FLOAT:
/* Floating point load/store */
return -4;
case ACCESS_RES:
/* lwarx, ldarx or srwcx. */
return -4;
case ACCESS_CACHE:
/* dcba, dcbt, dcbtst, dcbf, dcbi, dcbst, dcbz, or icbi */
/* Should make the instruction do no-op.
* As it already do no-op, it's quite easy :-)
*/
ctx->raddr = eaddr;
return 0;
case ACCESS_EXT:
/* eciwx or ecowx */
return -4;
default:
qemu_log("ERROR: instruction should not need "
"address translation\n");
return -4;
}
if ((rwx == 1 || ctx->key != 1) && (rwx == 0 || ctx->key != 0)) {
ctx->raddr = eaddr;
return 2;
} else {
return -2;
}
}
ctx->nx = !!(sr & SR32_NX);
vsid = sr & SR32_VSID;
target_page_bits = TARGET_PAGE_BITS;