pseries: Convert sPAPR TCEs to use generic IOMMU infrastructure

The pseries platform already contains an IOMMU implementation, since it is
essential for the platform's paravirtualized VIO devices.  This IOMMU
support is currently built into the implementation of the VIO "bus" and
the various VIO devices.

This patch converts this code to make use of the new common IOMMU
infrastructure.

We don't yet handle synchronization of map/unmap callbacks vs. invalidations,
this will require some complex interaction with the kernel and is not a
major concern at this stage.

Cc: Alex Graf <agraf@suse.de>

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 242 insertions, 0 deletions

diff --git a/hw/spapr_iommu.c b/hw/spapr_iommu.c
new file mode 100644
index 0000000000..5a769b9f4a
--- /dev/null
+++ b/hw/spapr_iommu.c
@@ -0,0 +1,242 @@
+/*
+ * QEMU sPAPR IOMMU (TCE) code
+ *
+ * Copyright (c) 2010 David Gibson, IBM Corporation <dwg@au1.ibm.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include "hw.h"
+#include "kvm.h"
+#include "qdev.h"
+#include "kvm_ppc.h"
+#include "dma.h"
+
+#include "hw/spapr.h"
+
+#include <libfdt.h>
+
+/* #define DEBUG_TCE */
+
+enum sPAPRTCEAccess {
+    SPAPR_TCE_FAULT = 0,
+    SPAPR_TCE_RO = 1,
+    SPAPR_TCE_WO = 2,
+    SPAPR_TCE_RW = 3,
+};
+
+typedef struct sPAPRTCETable sPAPRTCETable;
+
+struct sPAPRTCETable {
+    DMAContext dma;
+    uint32_t liobn;
+    uint32_t window_size;
+    sPAPRTCE *table;
+    int fd;
+    QLIST_ENTRY(sPAPRTCETable) list;
+};
+
+
+QLIST_HEAD(spapr_tce_tables, sPAPRTCETable) spapr_tce_tables;
+
+static sPAPRTCETable *spapr_tce_find_by_liobn(uint32_t liobn)
+{
+    sPAPRTCETable *tcet;
+
+    QLIST_FOREACH(tcet, &spapr_tce_tables, list) {
+        if (tcet->liobn == liobn) {
+            return tcet;
+        }
+    }
+
+    return NULL;
+}
+
+static int spapr_tce_translate(DMAContext *dma,
+                               dma_addr_t addr,
+                               target_phys_addr_t *paddr,
+                               target_phys_addr_t *len,
+                               DMADirection dir)
+{
+    sPAPRTCETable *tcet = DO_UPCAST(sPAPRTCETable, dma, dma);
+    enum sPAPRTCEAccess access = (dir == DMA_DIRECTION_FROM_DEVICE)
+        ? SPAPR_TCE_WO : SPAPR_TCE_RO;
+    uint64_t tce;
+
+#ifdef DEBUG_TCE
+    fprintf(stderr, "spapr_tce_translate liobn=0x%" PRIx32 " addr=0x"
+            DMA_ADDR_FMT "\n", tcet->liobn, addr);
+#endif
+
+    /* Check if we are in bound */
+    if (addr >= tcet->window_size) {
+#ifdef DEBUG_TCE
+        fprintf(stderr, "spapr_tce_translate out of bounds\n");
+#endif
+        return -EFAULT;
+    }
+
+    tce = tcet->table[addr >> SPAPR_TCE_PAGE_SHIFT].tce;
+
+    /* Check TCE */
+    if (!(tce & access)) {
+        return -EPERM;
+    }
+
+    /* How much til end of page ? */
+    *len = ((~addr) & SPAPR_TCE_PAGE_MASK) + 1;
+
+    /* Translate */
+    *paddr = (tce & ~SPAPR_TCE_PAGE_MASK) |
+        (addr & SPAPR_TCE_PAGE_MASK);
+
+#ifdef DEBUG_TCE
+    fprintf(stderr, " ->  *paddr=0x" TARGET_FMT_plx ", *len=0x"
+            TARGET_FMT_plx "\n", *paddr, *len);
+#endif
+
+    return 0;
+}
+
+DMAContext *spapr_tce_new_dma_context(uint32_t liobn, size_t window_size)
+{
+    sPAPRTCETable *tcet;
+
+    if (!window_size) {
+        return NULL;
+    }
+
+    tcet = g_malloc0(sizeof(*tcet));
+    dma_context_init(&tcet->dma, spapr_tce_translate, NULL, NULL);
+
+    tcet->liobn = liobn;
+    tcet->window_size = window_size;
+
+    if (kvm_enabled()) {
+        tcet->table = kvmppc_create_spapr_tce(liobn,
+                                              window_size,
+                                              &tcet->fd);
+    }
+
+    if (!tcet->table) {
+        size_t table_size = (window_size >> SPAPR_TCE_PAGE_SHIFT)
+            * sizeof(sPAPRTCE);
+        tcet->table = g_malloc0(table_size);
+    }
+
+#ifdef DEBUG_TCE
+    fprintf(stderr, "spapr_iommu: New TCE table, liobn=0x%x, context @ %p, "
+            "table @ %p, fd=%d\n", liobn, &tcet->dma, tcet->table, tcet->fd);
+#endif
+
+    QLIST_INSERT_HEAD(&spapr_tce_tables, tcet, list);
+
+    return &tcet->dma;
+}
+
+void spapr_tce_free(DMAContext *dma)
+{
+
+    if (dma) {
+        sPAPRTCETable *tcet = DO_UPCAST(sPAPRTCETable, dma, dma);
+
+        QLIST_REMOVE(tcet, list);
+
+        if (!kvm_enabled() ||
+            (kvmppc_remove_spapr_tce(tcet->table, tcet->fd,
+                                     tcet->window_size) != 0)) {
+            g_free(tcet->table);
+        }
+
+        g_free(tcet);
+    }
+}
+
+
+static target_ulong h_put_tce(CPUPPCState *env, sPAPREnvironment *spapr,
+                              target_ulong opcode, target_ulong *args)
+{
+    target_ulong liobn = args[0];
+    target_ulong ioba = args[1];
+    target_ulong tce = args[2];
+    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
+    sPAPRTCE *tcep;
+
+    if (liobn & 0xFFFFFFFF00000000ULL) {
+        hcall_dprintf("spapr_vio_put_tce on out-of-boundsw LIOBN "
+                      TARGET_FMT_lx "\n", liobn);
+        return H_PARAMETER;
+    }
+    if (!tcet) {
+        hcall_dprintf("spapr_vio_put_tce on non-existent LIOBN "
+                      TARGET_FMT_lx "\n", liobn);
+        return H_PARAMETER;
+    }
+
+    ioba &= ~(SPAPR_TCE_PAGE_SIZE - 1);
+
+#ifdef DEBUG_TCE
+    fprintf(stderr, "spapr_vio_put_tce on liobn=" TARGET_FMT_lx /*%s*/
+            "  ioba 0x" TARGET_FMT_lx "  TCE 0x" TARGET_FMT_lx "\n",
+            liobn, /*dev->qdev.id, */ioba, tce);
+#endif
+
+    if (ioba >= tcet->window_size) {
+        hcall_dprintf("spapr_vio_put_tce on out-of-boards IOBA 0x"
+                      TARGET_FMT_lx "\n", ioba);
+        return H_PARAMETER;
+    }
+
+    tcep = tcet->table + (ioba >> SPAPR_TCE_PAGE_SHIFT);
+    tcep->tce = tce;
+
+    return H_SUCCESS;
+}
+
+void spapr_iommu_init(void)
+{
+    QLIST_INIT(&spapr_tce_tables);
+
+    /* hcall-tce */
+    spapr_register_hypercall(H_PUT_TCE, h_put_tce);
+}
+
+int spapr_dma_dt(void *fdt, int node_off, const char *propname,
+                 DMAContext *dma)
+{
+    if (dma) {
+        sPAPRTCETable *tcet = DO_UPCAST(sPAPRTCETable, dma, dma);
+        uint32_t dma_prop[] = {cpu_to_be32(tcet->liobn),
+                               0, 0,
+                               0, cpu_to_be32(tcet->window_size)};
+        int ret;
+
+        ret = fdt_setprop_cell(fdt, node_off, "ibm,#dma-address-cells", 2);
+        if (ret < 0) {
+            return ret;
+        }
+
+        ret = fdt_setprop_cell(fdt, node_off, "ibm,#dma-size-cells", 2);
+        if (ret < 0) {
+            return ret;
+        }
+
+        ret = fdt_setprop(fdt, node_off, propname, dma_prop,
+                          sizeof(dma_prop));
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    return 0;
+}