iommu: Add universal DMA helper functions

[qemu.git] / dma.h

diff --git a/dma.h b/dma.h
index fe08b726057d0e6b886bd1e569760373ff106522..8912dfcb6e9703669372b6ebf7321cc50e9c8b17 100644 (file)
--- a/dma.h
+++ b/dma.h
@@ -14,6 +14,7 @@
 #include "hw/hw.h"
 #include "block.h"
 
+typedef struct DMAContext DMAContext;
 typedef struct ScatterGatherEntry ScatterGatherEntry;
 
 typedef enum {
@@ -34,6 +35,100 @@ typedef target_phys_addr_t dma_addr_t;
 #define DMA_ADDR_BITS TARGET_PHYS_ADDR_BITS
 #define DMA_ADDR_FMT TARGET_FMT_plx
 
+/* Checks that the given range of addresses is valid for DMA.  This is
+ * useful for certain cases, but usually you should just use
+ * dma_memory_{read,write}() and check for errors */
+static inline bool dma_memory_valid(DMAContext *dma, dma_addr_t addr,
+                                    dma_addr_t len, DMADirection dir)
+{
+    /* Stub version, with no iommu we assume all bus addresses are valid */
+    return true;
+}
+
+static inline int dma_memory_rw(DMAContext *dma, dma_addr_t addr,
+                                void *buf, dma_addr_t len, DMADirection dir)
+{
+    /* Stub version when we have no iommu support */
+    cpu_physical_memory_rw(addr, buf, (target_phys_addr_t)len,
+                           dir == DMA_DIRECTION_FROM_DEVICE);
+    return 0;
+}
+
+static inline int dma_memory_read(DMAContext *dma, dma_addr_t addr,
+                                  void *buf, dma_addr_t len)
+{
+    return dma_memory_rw(dma, addr, buf, len, DMA_DIRECTION_TO_DEVICE);
+}
+
+static inline int dma_memory_write(DMAContext *dma, dma_addr_t addr,
+                                   const void *buf, dma_addr_t len)
+{
+    return dma_memory_rw(dma, addr, (void *)buf, len,
+                         DMA_DIRECTION_FROM_DEVICE);
+}
+
+int dma_memory_set(DMAContext *dma, dma_addr_t addr, uint8_t c, dma_addr_t len);
+
+static inline void *dma_memory_map(DMAContext *dma,
+                                   dma_addr_t addr, dma_addr_t *len,
+                                   DMADirection dir)
+{
+    target_phys_addr_t xlen = *len;
+    void *p;
+
+    p = cpu_physical_memory_map(addr, &xlen,
+                                dir == DMA_DIRECTION_FROM_DEVICE);
+    *len = xlen;
+    return p;
+}
+
+static inline void dma_memory_unmap(DMAContext *dma,
+                                    void *buffer, dma_addr_t len,
+                                    DMADirection dir, dma_addr_t access_len)
+{
+    return cpu_physical_memory_unmap(buffer, (target_phys_addr_t)len,
+                                     dir == DMA_DIRECTION_FROM_DEVICE,
+                                     access_len);
+}
+
+#define DEFINE_LDST_DMA(_lname, _sname, _bits, _end) \
+    static inline uint##_bits##_t ld##_lname##_##_end##_dma(DMAContext *dma, \
+                                                            dma_addr_t addr) \
+    {                                                                   \
+        uint##_bits##_t val;                                            \
+        dma_memory_read(dma, addr, &val, (_bits) / 8);                  \
+        return _end##_bits##_to_cpu(val);                               \
+    }                                                                   \
+    static inline void st##_sname##_##_end##_dma(DMAContext *dma,       \
+                                                 dma_addr_t addr,       \
+                                                 uint##_bits##_t val)   \
+    {                                                                   \
+        val = cpu_to_##_end##_bits(val);                                \
+        dma_memory_write(dma, addr, &val, (_bits) / 8);                 \
+    }
+
+static inline uint8_t ldub_dma(DMAContext *dma, dma_addr_t addr)
+{
+    uint8_t val;
+
+    dma_memory_read(dma, addr, &val, 1);
+    return val;
+}
+
+static inline void stb_dma(DMAContext *dma, dma_addr_t addr, uint8_t val)
+{
+    dma_memory_write(dma, addr, &val, 1);
+}
+
+DEFINE_LDST_DMA(uw, w, 16, le);
+DEFINE_LDST_DMA(l, l, 32, le);
+DEFINE_LDST_DMA(q, q, 64, le);
+DEFINE_LDST_DMA(uw, w, 16, be);
+DEFINE_LDST_DMA(l, l, 32, be);
+DEFINE_LDST_DMA(q, q, 64, be);
+
+#undef DEFINE_LDST_DMA
+
 struct ScatterGatherEntry {
     dma_addr_t base;
     dma_addr_t len;