[Qemu-ppc] [PATCH 1/3] powerpc iommu: multiple TCE requests enabled

[Alexey Kardashevskiy]

Currently only single TCE entry per requiest is supported (H_PUT_TCE).
However PAPR+ specification allows multiple entry requests such as
H_PUT_TCE_INDIRECT and H_STUFFF_TCE. Having less transitions to the host
kernel via ioctls, support of these calls can accelerate IOMMU operations.

The patch adds a check for the KVM_CAP_PPC_MULTITCE capability and
if it is supported, QEMU adds the "call-multi-tce" property to hypertas
list which triggers the guest to use H_PUT_TCE_INDIRECT and H_STUFF_TCE
instead of H_PUT_TCE.

Signed-off-by: Alexey Kardashevskiy <address@hidden>

Conflicts:
        hw/spapr_iommu.c
        linux-headers/linux/kvm.h
---
 hw/spapr.c                |   12 ++++++--
 hw/spapr_iommu.c          |   71 +++++++++++++++++++++++++++++++++++++++++++++
 linux-headers/linux/kvm.h |    1 +
 3 files changed, 82 insertions(+), 2 deletions(-)

diff --git a/hw/spapr.c b/hw/spapr.c
index 2ec0cd0..231a7b6 100644
--- a/hw/spapr.c
+++ b/hw/spapr.c
@@ -233,6 +233,9 @@ static void *spapr_create_fdt_skel(const char *cpu_model,
     CPUPPCState *env;
     uint32_t start_prop = cpu_to_be32(initrd_base);
     uint32_t end_prop = cpu_to_be32(initrd_base + initrd_size);
+    char hypertas_propm[] = 
"hcall-pft\0hcall-term\0hcall-dabr\0hcall-interrupt"
+        "\0hcall-tce\0hcall-vio\0hcall-splpar\0hcall-bulk"
+        "\0hcall-multi-tce";
     char hypertas_prop[] = "hcall-pft\0hcall-term\0hcall-dabr\0hcall-interrupt"
         "\0hcall-tce\0hcall-vio\0hcall-splpar\0hcall-bulk";
     char qemu_hypertas_prop[] = "hcall-memop1";
@@ -406,8 +409,13 @@ static void *spapr_create_fdt_skel(const char *cpu_model,
     /* RTAS */
     _FDT((fdt_begin_node(fdt, "rtas")));
 
-    _FDT((fdt_property(fdt, "ibm,hypertas-functions", hypertas_prop,
-                       sizeof(hypertas_prop))));
+    if (kvm_check_extension(kvm_state, KVM_CAP_PPC_MULTITCE)) {
+        _FDT((fdt_property(fdt, "ibm,hypertas-functions", hypertas_propm,
+                           sizeof(hypertas_propm))));
+    } else {
+        _FDT((fdt_property(fdt, "ibm,hypertas-functions", hypertas_prop,
+                           sizeof(hypertas_prop))));
+    }
     _FDT((fdt_property(fdt, "qemu,hypertas-functions", qemu_hypertas_prop,
                        sizeof(qemu_hypertas_prop))));
 
diff --git a/hw/spapr_iommu.c b/hw/spapr_iommu.c
index 5904c1c..94630c1 100644
--- a/hw/spapr_iommu.c
+++ b/hw/spapr_iommu.c
@@ -234,6 +234,75 @@ static target_ulong put_tce_emu(sPAPRTCETable *tcet, 
target_ulong ioba,
     return H_SUCCESS;
 }
 
+static target_ulong h_put_tce_indirect(PowerPCCPU *cpu,
+                                       sPAPREnvironment *spapr,
+                                       target_ulong opcode, target_ulong *args)
+{
+    int i;
+    target_ulong liobn = args[0];
+    target_ulong ioba = args[1];
+    target_ulong tce_list = args[2];
+    target_ulong npages = args[3];
+    target_ulong *tces, ret = 0;
+    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
+
+    if (liobn & 0xFFFFFFFF00000000ULL) {
+        hcall_dprintf("spapr_vio_put_tce on out-of-boundsw LIOBN "
+                      TARGET_FMT_lx "\n", liobn);
+        return H_PARAMETER;
+    }
+
+    tces = (target_ulong *) qemu_get_ram_ptr(tce_list & ~SPAPR_TCE_PAGE_MASK);
+
+    if (tcet) {
+        for (i = 0; (i < npages) && !ret; ++i, ioba += SPAPR_TCE_PAGE_SIZE) {
+            ret = put_tce_emu(tcet, ioba, tces[i]);
+        }
+        return ret;
+    }
+#ifdef DEBUG_TCE
+    fprintf(stderr, "%s on liobn=" TARGET_FMT_lx /*%s*/
+            "  ioba 0x" TARGET_FMT_lx "  TCE 0x" TARGET_FMT_lx "\n",
+            __func__, liobn, /*dev->qdev.id, */ioba, tce);
+#endif
+
+    return H_PARAMETER;
+}
+
+static target_ulong h_stuff_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
+                              target_ulong opcode, target_ulong *args)
+{
+    int i;
+    target_ulong liobn = args[0];
+    target_ulong ioba = args[1];
+    target_ulong tce_value = args[2];
+    target_ulong npages = args[3];
+    target_ulong ret = 0;
+    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
+
+    if (liobn & 0xFFFFFFFF00000000ULL) {
+        hcall_dprintf("spapr_vio_put_tce on out-of-boundsw LIOBN "
+                      TARGET_FMT_lx "\n", liobn);
+        return H_PARAMETER;
+    }
+
+    ioba &= ~(SPAPR_TCE_PAGE_SIZE - 1);
+
+    if (tcet) {
+        for (i = 0; (i < npages) && !ret; ++i, ioba += SPAPR_TCE_PAGE_SIZE) {
+            ret = put_tce_emu(tcet, ioba, tce_value);
+        }
+        return ret;
+    }
+#ifdef DEBUG_TCE
+    fprintf(stderr, "%s on liobn=" TARGET_FMT_lx /*%s*/
+            "  ioba 0x" TARGET_FMT_lx "  TCE 0x" TARGET_FMT_lx "\n",
+            __func__, liobn, /*dev->qdev.id, */ioba, tce);
+#endif
+
+    return H_PARAMETER;
+}
+
 static target_ulong h_put_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
                               target_ulong opcode, target_ulong *args)
 {
@@ -268,6 +337,8 @@ void spapr_iommu_init(void)
 
     /* hcall-tce */
     spapr_register_hypercall(H_PUT_TCE, h_put_tce);
+    spapr_register_hypercall(H_PUT_TCE_INDIRECT, h_put_tce_indirect);
+    spapr_register_hypercall(H_STUFF_TCE, h_stuff_tce);
 }
 
 int spapr_dma_dt(void *fdt, int node_off, const char *propname,
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 56077d5..8aff3b0 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -633,6 +633,7 @@ struct kvm_ppc_smmu_info {
 #define KVM_CAP_PPC_RTAS 84
 #define KVM_CAP_SPAPR_XICS 85
 #define KVM_CAP_PPC_HTAB_FD 86
+#define KVM_CAP_PPC_MULTITCE 87
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
1.7.10.4