
References: bsc#1135799

# Commit c69363b2ac7e5ed88908a304e6903f5842c9805e
# Date 2019-07-31 13:14:27 +0200
# Author Jan Beulich <jbeulich@suse.com>
# Committer Jan Beulich <jbeulich@suse.com>
AMD/IOMMU: use bit field for extended feature register

This also takes care of several of the shift values wrongly having been
specified as hex rather than dec.

Take the opportunity and
- replace a readl() pair by a single readq(),
- add further fields.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Brian Woods <brian.woods@amd.com>

--- a/xen/drivers/passthrough/amd/iommu_detect.c
+++ b/xen/drivers/passthrough/amd/iommu_detect.c
@@ -60,49 +60,76 @@ static int __init get_iommu_capabilities
 
 void __init get_iommu_features(struct amd_iommu *iommu)
 {
-    u32 low, high;
-    int i = 0 ;
     const struct amd_iommu *first;
-    static const char *__initdata feature_str[] = {
-        "- Prefetch Pages Command", 
-        "- Peripheral Page Service Request", 
-        "- X2APIC Supported", 
-        "- NX bit Supported", 
-        "- Guest Translation", 
-        "- Reserved bit [5]",
-        "- Invalidate All Command", 
-        "- Guest APIC supported", 
-        "- Hardware Error Registers", 
-        "- Performance Counters", 
-        NULL
-    };
-
     ASSERT( iommu->mmio_base );
 
     if ( !iommu_has_cap(iommu, PCI_CAP_EFRSUP_SHIFT) )
     {
-        iommu->features = 0;
+        iommu->features.raw = 0;
         return;
     }
 
-    low = readl(iommu->mmio_base + IOMMU_EXT_FEATURE_MMIO_OFFSET);
-    high = readl(iommu->mmio_base + IOMMU_EXT_FEATURE_MMIO_OFFSET + 4);
-
-    iommu->features = ((u64)high << 32) | low;
+    iommu->features.raw =
+        readq(iommu->mmio_base + IOMMU_EXT_FEATURE_MMIO_OFFSET);
 
     /* Don't log the same set of features over and over. */
     first = list_first_entry(&amd_iommu_head, struct amd_iommu, list);
-    if ( iommu != first && iommu->features == first->features )
+    if ( iommu != first && iommu->features.raw == first->features.raw )
         return;
 
     printk("AMD-Vi: IOMMU Extended Features:\n");
 
-    while ( feature_str[i] )
+#define FEAT(fld, str) do {                                    \
+    if ( --((union amd_iommu_ext_features){}).flds.fld > 1 )   \
+        printk( "- " str ": %#x\n", iommu->features.flds.fld); \
+    else if ( iommu->features.flds.fld )                       \
+        printk( "- " str "\n");                                \
+} while ( false )
+
+    FEAT(pref_sup,           "Prefetch Pages Command");
+    FEAT(ppr_sup,            "Peripheral Page Service Request");
+    FEAT(xt_sup,             "x2APIC");
+    FEAT(nx_sup,             "NX bit");
+    FEAT(gappi_sup,          "Guest APIC Physical Processor Interrupt");
+    FEAT(ia_sup,             "Invalidate All Command");
+    FEAT(ga_sup,             "Guest APIC");
+    FEAT(he_sup,             "Hardware Error Registers");
+    FEAT(pc_sup,             "Performance Counters");
+    FEAT(hats,               "Host Address Translation Size");
+
+    if ( iommu->features.flds.gt_sup )
     {
-        if ( amd_iommu_has_feature(iommu, i) )
-            printk( " %s\n", feature_str[i]);
-        i++;
+        FEAT(gats,           "Guest Address Translation Size");
+        FEAT(glx_sup,        "Guest CR3 Root Table Level");
+        FEAT(pas_max,        "Maximum PASID");
     }
+
+    FEAT(smif_sup,           "SMI Filter Register");
+    FEAT(smif_rc,            "SMI Filter Register Count");
+    FEAT(gam_sup,            "Guest Virtual APIC Modes");
+    FEAT(dual_ppr_log_sup,   "Dual PPR Log");
+    FEAT(dual_event_log_sup, "Dual Event Log");
+    FEAT(sats_sup,           "Secure ATS");
+    FEAT(us_sup,             "User / Supervisor Page Protection");
+    FEAT(dev_tbl_seg_sup,    "Device Table Segmentation");
+    FEAT(ppr_early_of_sup,   "PPR Log Overflow Early Warning");
+    FEAT(ppr_auto_rsp_sup,   "PPR Automatic Response");
+    FEAT(marc_sup,           "Memory Access Routing and Control");
+    FEAT(blk_stop_mrk_sup,   "Block StopMark Message");
+    FEAT(perf_opt_sup ,      "Performance Optimization");
+    FEAT(msi_cap_mmio_sup,   "MSI Capability MMIO Access");
+    FEAT(gio_sup,            "Guest I/O Protection");
+    FEAT(ha_sup,             "Host Access");
+    FEAT(eph_sup,            "Enhanced PPR Handling");
+    FEAT(attr_fw_sup,        "Attribute Forward");
+    FEAT(hd_sup,             "Host Dirty");
+    FEAT(inv_iotlb_type_sup, "Invalidate IOTLB Type");
+    FEAT(viommu_sup,         "Virtualized IOMMU");
+    FEAT(vm_guard_io_sup,    "VMGuard I/O Support");
+    FEAT(vm_table_size,      "VM Table Size");
+    FEAT(ga_update_dis_sup,  "Guest Access Bit Update Disable");
+
+#undef FEAT
 }
 
 int __init amd_iommu_detect_one_acpi(
--- a/xen/drivers/passthrough/amd/iommu_guest.c
+++ b/xen/drivers/passthrough/amd/iommu_guest.c
@@ -667,7 +667,7 @@ static uint64_t iommu_mmio_read64(struct
         val = reg_to_u64(iommu->reg_status);
         break;
     case IOMMU_EXT_FEATURE_MMIO_OFFSET:
-        val = reg_to_u64(iommu->reg_ext_feature);
+        val = iommu->reg_ext_feature.raw;
         break;
 
     default:
@@ -831,39 +831,26 @@ int guest_iommu_set_base(struct domain *
 /* Initialize mmio read only bits */
 static void guest_iommu_reg_init(struct guest_iommu *iommu)
 {
-    uint32_t lower, upper;
+    union amd_iommu_ext_features ef = {
+        /* Support prefetch */
+        .flds.pref_sup = 1,
+        /* Support PPR log */
+        .flds.ppr_sup = 1,
+        /* Support guest translation */
+        .flds.gt_sup = 1,
+        /* Support invalidate all command */
+        .flds.ia_sup = 1,
+        /* Host translation size has 6 levels */
+        .flds.hats = HOST_ADDRESS_SIZE_6_LEVEL,
+        /* Guest translation size has 6 levels */
+        .flds.gats = GUEST_ADDRESS_SIZE_6_LEVEL,
+        /* Single level gCR3 */
+        .flds.glx_sup = GUEST_CR3_1_LEVEL,
+        /* 9 bit PASID */
+        .flds.pas_max = PASMAX_9_bit,
+    };
 
-    lower = upper = 0;
-    /* Support prefetch */
-    iommu_set_bit(&lower,IOMMU_EXT_FEATURE_PREFSUP_SHIFT);
-    /* Support PPR log */
-    iommu_set_bit(&lower,IOMMU_EXT_FEATURE_PPRSUP_SHIFT);
-    /* Support guest translation */
-    iommu_set_bit(&lower,IOMMU_EXT_FEATURE_GTSUP_SHIFT);
-    /* Support invalidate all command */
-    iommu_set_bit(&lower,IOMMU_EXT_FEATURE_IASUP_SHIFT);
-
-    /* Host translation size has 6 levels */
-    set_field_in_reg_u32(HOST_ADDRESS_SIZE_6_LEVEL, lower,
-                         IOMMU_EXT_FEATURE_HATS_MASK,
-                         IOMMU_EXT_FEATURE_HATS_SHIFT,
-                         &lower);
-    /* Guest translation size has 6 levels */
-    set_field_in_reg_u32(GUEST_ADDRESS_SIZE_6_LEVEL, lower,
-                         IOMMU_EXT_FEATURE_GATS_MASK,
-                         IOMMU_EXT_FEATURE_GATS_SHIFT,
-                         &lower);
-    /* Single level gCR3 */
-    set_field_in_reg_u32(GUEST_CR3_1_LEVEL, lower,
-                         IOMMU_EXT_FEATURE_GLXSUP_MASK,
-                         IOMMU_EXT_FEATURE_GLXSUP_SHIFT, &lower);
-    /* 9 bit PASID */
-    set_field_in_reg_u32(PASMAX_9_bit, upper,
-                         IOMMU_EXT_FEATURE_PASMAX_MASK,
-                         IOMMU_EXT_FEATURE_PASMAX_SHIFT, &upper);
-
-    iommu->reg_ext_feature.lo = lower;
-    iommu->reg_ext_feature.hi = upper;
+    iommu->reg_ext_feature = ef;
 }
 
 static int guest_iommu_mmio_range(struct vcpu *v, unsigned long addr)
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -883,7 +883,7 @@ static void enable_iommu(struct amd_iomm
     register_iommu_event_log_in_mmio_space(iommu);
     register_iommu_exclusion_range(iommu);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_PPRSUP_SHIFT) )
+    if ( iommu->features.flds.ppr_sup )
         register_iommu_ppr_log_in_mmio_space(iommu);
 
     desc = irq_to_desc(iommu->msi.irq);
@@ -897,15 +897,15 @@ static void enable_iommu(struct amd_iomm
     set_iommu_command_buffer_control(iommu, IOMMU_CONTROL_ENABLED);
     set_iommu_event_log_control(iommu, IOMMU_CONTROL_ENABLED);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_PPRSUP_SHIFT) )
+    if ( iommu->features.flds.ppr_sup )
         set_iommu_ppr_log_control(iommu, IOMMU_CONTROL_ENABLED);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_GTSUP_SHIFT) )
+    if ( iommu->features.flds.gt_sup )
         set_iommu_guest_translation_control(iommu, IOMMU_CONTROL_ENABLED);
 
     set_iommu_translation_control(iommu, IOMMU_CONTROL_ENABLED);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_IASUP_SHIFT) )
+    if ( iommu->features.flds.ia_sup )
         amd_iommu_flush_all_caches(iommu);
 
     iommu->enabled = 1;
@@ -928,10 +928,10 @@ static void disable_iommu(struct amd_iom
     set_iommu_command_buffer_control(iommu, IOMMU_CONTROL_DISABLED);
     set_iommu_event_log_control(iommu, IOMMU_CONTROL_DISABLED);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_PPRSUP_SHIFT) )
+    if ( iommu->features.flds.ppr_sup )
         set_iommu_ppr_log_control(iommu, IOMMU_CONTROL_DISABLED);
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_GTSUP_SHIFT) )
+    if ( iommu->features.flds.gt_sup )
         set_iommu_guest_translation_control(iommu, IOMMU_CONTROL_DISABLED);
 
     set_iommu_translation_control(iommu, IOMMU_CONTROL_DISABLED);
@@ -1029,7 +1029,7 @@ static int __init amd_iommu_init_one(str
 
     get_iommu_features(iommu);
 
-    if ( iommu->features )
+    if ( iommu->features.raw )
         iommuv2_enabled = 1;
 
     if ( allocate_cmd_buffer(iommu) == NULL )
@@ -1038,9 +1038,8 @@ static int __init amd_iommu_init_one(str
     if ( allocate_event_log(iommu) == NULL )
         goto error_out;
 
-    if ( amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_PPRSUP_SHIFT) )
-        if ( allocate_ppr_log(iommu) == NULL )
-            goto error_out;
+    if ( iommu->features.flds.ppr_sup && !allocate_ppr_log(iommu) )
+        goto error_out;
 
     if ( !set_iommu_interrupt_handler(iommu) )
         goto error_out;
@@ -1396,7 +1395,7 @@ void amd_iommu_resume(void)
     }
 
     /* flush all cache entries after iommu re-enabled */
-    if ( !amd_iommu_has_feature(iommu, IOMMU_EXT_FEATURE_IASUP_SHIFT) )
+    if ( !iommu->features.flds.ia_sup )
     {
         invalidate_all_devices();
         invalidate_all_domain_pages();
--- a/xen/include/asm-x86/amd-iommu.h
+++ b/xen/include/asm-x86/amd-iommu.h
@@ -88,7 +88,7 @@ struct amd_iommu {
     iommu_cap_t cap;
 
     u8 ht_flags;
-    u64 features;
+    union amd_iommu_ext_features features;
 
     void *mmio_base;
     unsigned long mmio_base_phys;
@@ -180,7 +180,7 @@ struct guest_iommu {
     /* MMIO regs */
     struct mmio_reg         reg_ctrl;              /* MMIO offset 0018h */
     struct mmio_reg         reg_status;            /* MMIO offset 2020h */
-    struct mmio_reg         reg_ext_feature;       /* MMIO offset 0030h */
+    union amd_iommu_ext_features reg_ext_feature;  /* MMIO offset 0030h */
 
     /* guest interrupt settings */
     struct guest_iommu_msi  msi;
--- a/xen/include/asm-x86/hvm/svm/amd-iommu-defs.h
+++ b/xen/include/asm-x86/hvm/svm/amd-iommu-defs.h
@@ -362,26 +362,57 @@
 #define IOMMU_EXCLUSION_LIMIT_HIGH_MASK		0xFFFFFFFF
 #define IOMMU_EXCLUSION_LIMIT_HIGH_SHIFT	0
 
-/* Extended Feature Register*/
+/* Extended Feature Register */
 #define IOMMU_EXT_FEATURE_MMIO_OFFSET                   0x30
-#define IOMMU_EXT_FEATURE_PREFSUP_SHIFT                 0x0
-#define IOMMU_EXT_FEATURE_PPRSUP_SHIFT                  0x1
-#define IOMMU_EXT_FEATURE_XTSUP_SHIFT                   0x2
-#define IOMMU_EXT_FEATURE_NXSUP_SHIFT                   0x3
-#define IOMMU_EXT_FEATURE_GTSUP_SHIFT                   0x4
-#define IOMMU_EXT_FEATURE_IASUP_SHIFT                   0x6
-#define IOMMU_EXT_FEATURE_GASUP_SHIFT                   0x7
-#define IOMMU_EXT_FEATURE_HESUP_SHIFT                   0x8
-#define IOMMU_EXT_FEATURE_PCSUP_SHIFT                   0x9
-#define IOMMU_EXT_FEATURE_HATS_SHIFT                    0x10
-#define IOMMU_EXT_FEATURE_HATS_MASK                     0x00000C00
-#define IOMMU_EXT_FEATURE_GATS_SHIFT                    0x12
-#define IOMMU_EXT_FEATURE_GATS_MASK                     0x00003000
-#define IOMMU_EXT_FEATURE_GLXSUP_SHIFT                  0x14
-#define IOMMU_EXT_FEATURE_GLXSUP_MASK                   0x0000C000
 
-#define IOMMU_EXT_FEATURE_PASMAX_SHIFT                  0x0
-#define IOMMU_EXT_FEATURE_PASMAX_MASK                   0x0000001F
+union amd_iommu_ext_features {
+    uint64_t raw;
+    struct {
+        unsigned int pref_sup:1;
+        unsigned int ppr_sup:1;
+        unsigned int xt_sup:1;
+        unsigned int nx_sup:1;
+        unsigned int gt_sup:1;
+        unsigned int gappi_sup:1;
+        unsigned int ia_sup:1;
+        unsigned int ga_sup:1;
+        unsigned int he_sup:1;
+        unsigned int pc_sup:1;
+        unsigned int hats:2;
+        unsigned int gats:2;
+        unsigned int glx_sup:2;
+        unsigned int smif_sup:2;
+        unsigned int smif_rc:3;
+        unsigned int gam_sup:3;
+        unsigned int dual_ppr_log_sup:2;
+        unsigned int :2;
+        unsigned int dual_event_log_sup:2;
+        unsigned int :1;
+        unsigned int sats_sup:1;
+        unsigned int pas_max:5;
+        unsigned int us_sup:1;
+        unsigned int dev_tbl_seg_sup:2;
+        unsigned int ppr_early_of_sup:1;
+        unsigned int ppr_auto_rsp_sup:1;
+        unsigned int marc_sup:2;
+        unsigned int blk_stop_mrk_sup:1;
+        unsigned int perf_opt_sup:1;
+        unsigned int msi_cap_mmio_sup:1;
+        unsigned int :1;
+        unsigned int gio_sup:1;
+        unsigned int ha_sup:1;
+        unsigned int eph_sup:1;
+        unsigned int attr_fw_sup:1;
+        unsigned int hd_sup:1;
+        unsigned int :1;
+        unsigned int inv_iotlb_type_sup:1;
+        unsigned int viommu_sup:1;
+        unsigned int vm_guard_io_sup:1;
+        unsigned int vm_table_size:4;
+        unsigned int ga_update_dis_sup:1;
+        unsigned int :2;
+    } flds;
+};
 
 /* Status Register*/
 #define IOMMU_STATUS_MMIO_OFFSET		0x2020
--- a/xen/include/asm-x86/hvm/svm/amd-iommu-proto.h
+++ b/xen/include/asm-x86/hvm/svm/amd-iommu-proto.h
@@ -223,13 +223,6 @@ static inline int iommu_has_cap(struct a
     return !!(iommu->cap.header & (1u << bit));
 }
 
-static inline int amd_iommu_has_feature(struct amd_iommu *iommu, uint32_t bit)
-{
-    if ( !iommu_has_cap(iommu, PCI_CAP_EFRSUP_SHIFT) )
-        return 0;
-    return !!(iommu->features & (1U << bit));
-}
-
 /* access tail or head pointer of ring buffer */
 static inline uint32_t iommu_get_rb_pointer(uint32_t reg)
 {
