diff mbox

[01/14] i386: add private_features

Message ID 200909091541.AA00084@YOUR-BD18D6DD63.m1.interq.or.jp
State Superseded
Headers show

Commit Message

武田 =?ISO-2022-JP?B?IBskQj1TTGkbKEI=?= Sept. 9, 2009, 3:41 p.m. UTC 
This patch is to add private_features to i386.
It is like cpuid_ext*_features, but is used for any features
not defined in CPUID.

And "a20mask" feature is defined in private_features.
It is for a20 adrdress mask of PC-98 family.

Comments

Alexander Graf Sept. 10, 2009, 7:33 a.m. UTC | #1 
On 09.09.2009, at 17:41, 武田 俊也 wrote:

> This patch is to add private_features to i386.
> It is like cpuid_ext*_features, but is used for any features
> not defined in CPUID.
>
> And "a20mask" feature is defined in private_features.
> It is for a20 adrdress mask of PC-98 family.

Due to the lack of a 00/14 conver letter, I'll just reply here.

Great job! Most of the code looks rather isolated, so I don't see any  
problem with including it in qemu. I gave you inline comments on the  
code where I see problems, as it collides with existing code.

In general having pc98 support could prove really useful, as there are  
few pc98 emulators around.

As for new files, please post them as patches as well. Since you're  
already using git, I'd recommend to look at "git format-patch", which  
creates really nice patches if you have committed things properly into  
the git tree before.

Anthony, please comment on this series as well, since you're the de- 
facto maintainer of x86 now I guess :-).

Alex
diff mbox

Patch

diff -ur a/target-i386/cpu.h b/target-i386/cpu.h
--- a/target-i386/cpu.h	Tue Sep  8 21:26:50 2009
+++ b/target-i386/cpu.h	Wed Sep  9 21:52:30 2009
@@ -404,6 +404,8 @@ 
 #define CPUID_EXT3_IBS     (1 << 10)
 #define CPUID_EXT3_SKINIT  (1 << 12)
 
+#define PRIVATE_FEATURE_A20MASK (1 << 0)
+
 #define CPUID_VENDOR_INTEL_1 0x756e6547 /* "Genu" */
 #define CPUID_VENDOR_INTEL_2 0x49656e69 /* "ineI" */
 #define CPUID_VENDOR_INTEL_3 0x6c65746e /* "ntel" */
@@ -673,6 +675,9 @@ 
     uint32_t cpuid_ext3_features;
     uint32_t cpuid_apic_id;
     int cpuid_vendor_override;
+
+    /* private features not defined in CPUID */
+    uint32_t private_features;
 
     /* MTRRs */
     uint64_t mtrr_fixed[11];
diff -ur a/target-i386/helper.c b/target-i386/helper.c
--- a/target-i386/helper.c	Tue Sep  8 21:26:51 2009
+++ b/target-i386/helper.c	Wed Sep  9 21:52:24 2009
@@ -57,11 +57,18 @@ 
     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 };
+static const char *private_feature_name[] = {
+    "a20mask", NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+};
 
 static void add_flagname_to_bitmaps(const char *flagname, uint32_t *features,
                                     uint32_t *ext_features,
                                     uint32_t *ext2_features,
-                                    uint32_t *ext3_features)
+                                    uint32_t *ext3_features,
+                                    uint32_t *private_features)
 {
     int i;
     int found = 0;
@@ -86,6 +93,11 @@ 
             *ext3_features |= 1 << i;
             found = 1;
         }
+    for ( i = 0 ; i < 32 ; i++ )
+        if (private_feature_name[i] && !strcmp (flagname, private_feature_name[i])) {
+            *private_features |= 1 << i;
+            found = 1;
+        }
     if (!found) {
         fprintf(stderr, "CPU feature %s not found\n", flagname);
     }
@@ -99,6 +111,7 @@ 
     int model;
     int stepping;
     uint32_t features, ext_features, ext2_features, ext3_features;
+    uint32_t private_features;
     uint32_t xlevel;
     char model_id[48];
     int vendor_override;
@@ -375,6 +388,7 @@ 
     char *featurestr, *name = strtok(s, ",");
     uint32_t plus_features = 0, plus_ext_features = 0, plus_ext2_features = 0, plus_ext3_features = 0;
     uint32_t minus_features = 0, minus_ext_features = 0, minus_ext2_features = 0, minus_ext3_features = 0;
+    uint32_t plus_private_features = 0, minus_private_features = 0;
     uint32_t numvalue;
 
     def = NULL;
@@ -393,16 +407,21 @@ 
     }
 
     add_flagname_to_bitmaps("hypervisor", &plus_features,
-        &plus_ext_features, &plus_ext2_features, &plus_ext3_features);
+        &plus_ext_features, &plus_ext2_features, &plus_ext3_features,
+        &plus_private_features);
 
     featurestr = strtok(NULL, ",");
 
     while (featurestr) {
         char *val;
         if (featurestr[0] == '+') {
-            add_flagname_to_bitmaps(featurestr + 1, &plus_features, &plus_ext_features, &plus_ext2_features, &plus_ext3_features);
+            add_flagname_to_bitmaps(featurestr + 1, &plus_features,
+                &plus_ext_features, &plus_ext2_features, &plus_ext3_features,
+                &plus_private_features);
         } else if (featurestr[0] == '-') {
-            add_flagname_to_bitmaps(featurestr + 1, &minus_features, &minus_ext_features, &minus_ext2_features, &minus_ext3_features);
+            add_flagname_to_bitmaps(featurestr + 1, &minus_features,
+                &minus_ext_features, &minus_ext2_features, &minus_ext3_features,
+                &minus_private_features);
         } else if ((val = strchr(featurestr, '='))) {
             *val = 0; val++;
             if (!strcmp(featurestr, "family")) {
@@ -479,10 +498,12 @@ 
     x86_cpu_def->ext_features |= plus_ext_features;
     x86_cpu_def->ext2_features |= plus_ext2_features;
     x86_cpu_def->ext3_features |= plus_ext3_features;
+    x86_cpu_def->private_features |= plus_private_features;
     x86_cpu_def->features &= ~minus_features;
     x86_cpu_def->ext_features &= ~minus_ext_features;
     x86_cpu_def->ext2_features &= ~minus_ext2_features;
     x86_cpu_def->ext3_features &= ~minus_ext3_features;
+    x86_cpu_def->private_features &= ~minus_private_features;
     free(s);
     return 0;
 
@@ -528,6 +549,7 @@ 
     env->cpuid_ext2_features = def->ext2_features;
     env->cpuid_xlevel = def->xlevel;
     env->cpuid_ext3_features = def->ext3_features;
+    env->private_features = def->private_features;
     {
         const char *model_id = def->model_id;
         int c, len, i;
@@ -569,7 +591,11 @@ 
     env->hflags2 |= HF2_GIF_MASK;
 
     cpu_x86_update_cr0(env, 0x60000010);
-    env->a20_mask = ~0x0;
+    if (env->private_features & PRIVATE_FEATURE_A20MASK) {
+        env->a20_mask = 0xfffff;
+    } else {
+        env->a20_mask = ~0x0;
+    }
     env->smbase = 0x30000;
 
     env->idt.limit = 0xffff;
@@ -939,7 +965,15 @@ 
         /* when a20 is changed, all the MMU mappings are invalid, so
            we must flush everything */
         tlb_flush(env, 1);
-        env->a20_mask = (~0x100000) | (a20_state << 20);
+        if (env->private_features & PRIVATE_FEATURE_A20MASK) {
+            if (a20_state) {
+                env->a20_mask = ~0x0;
+            } else {
+                env->a20_mask = 0xfffff;
+            }
+        } else {
+            env->a20_mask = (~0x100000) | (a20_state << 20);
+        }
     }
 }