libqos: Implement mmio accessors in terms of mem{read,write}

In the libqos PCI code we now have accessors both for registers (byte
significance preserving) and for streaming data (byte address order
preserving).  These exist in both the interface for qtest drivers and in
the machine specific backends.

However, the register-style accessors aren't actually necessary in the
backend.  They can be implemented in terms of the byte address order
preserving accessors by the libqos wrappers.  This works because PCI is
always little endian.

This does assume that the back end byte address order preserving accessors
will perform the equivalent of a single bus transaction for short lengths.
This is the case, and in fact they currently end up using the same
cpu_physical_memory_rw() implementation within the qtest accelerator.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>

4 files changed, 14 insertions, 96 deletions

diff --git a/tests/libqos/pci-pc.c b/tests/libqos/pci-pc.c
index 84aee25..849ea56 100644
--- a/tests/libqos/pci-pc.c
+++ b/tests/libqos/pci-pc.c
@@ -32,61 +32,31 @@ static uint8_t qpci_pc_pio_readb(QPCIBus *bus, uint32_t addr)
     return inb(addr);
 }
 
-static uint8_t qpci_pc_mmio_readb(QPCIBus *bus, uint32_t addr)
-{
-    return readb(addr);
-}
-
 static void qpci_pc_pio_writeb(QPCIBus *bus, uint32_t addr, uint8_t val)
 {
     outb(addr, val);
 }
 
-static void qpci_pc_mmio_writeb(QPCIBus *bus, uint32_t addr, uint8_t val)
-{
-    writeb(addr, val);
-}
-
 static uint16_t qpci_pc_pio_readw(QPCIBus *bus, uint32_t addr)
 {
     return inw(addr);
 }
 
-static uint16_t qpci_pc_mmio_readw(QPCIBus *bus, uint32_t addr)
-{
-    return readw(addr);
-}
-
 static void qpci_pc_pio_writew(QPCIBus *bus, uint32_t addr, uint16_t val)
 {
     outw(addr, val);
 }
 
-static void qpci_pc_mmio_writew(QPCIBus *bus, uint32_t addr, uint16_t val)
-{
-    writew(addr, val);
-}
-
 static uint32_t qpci_pc_pio_readl(QPCIBus *bus, uint32_t addr)
 {
     return inl(addr);
 }
 
-static uint32_t qpci_pc_mmio_readl(QPCIBus *bus, uint32_t addr)
-{
-    return readl(addr);
-}
-
 static void qpci_pc_pio_writel(QPCIBus *bus, uint32_t addr, uint32_t val)
 {
     outl(addr, val);
 }
 
-static void qpci_pc_mmio_writel(QPCIBus *bus, uint32_t addr, uint32_t val)
-{
-    writel(addr, val);
-}
-
 static void qpci_pc_memread(QPCIBus *bus, uint32_t addr, void *buf, size_t len)
 {
     memread(addr, buf, len);
@@ -148,14 +118,6 @@ QPCIBus *qpci_init_pc(QGuestAllocator *alloc)
     ret->bus.pio_writew = qpci_pc_pio_writew;
     ret->bus.pio_writel = qpci_pc_pio_writel;
 
-    ret->bus.mmio_readb = qpci_pc_mmio_readb;
-    ret->bus.mmio_readw = qpci_pc_mmio_readw;
-    ret->bus.mmio_readl = qpci_pc_mmio_readl;
-
-    ret->bus.mmio_writeb = qpci_pc_mmio_writeb;
-    ret->bus.mmio_writew = qpci_pc_mmio_writew;
-    ret->bus.mmio_writel = qpci_pc_mmio_writel;
-
     ret->bus.memread = qpci_pc_memread;
     ret->bus.memwrite = qpci_pc_memwrite;
 
diff --git a/tests/libqos/pci-spapr.c b/tests/libqos/pci-spapr.c
index ad12c2e..f26488a 100644
--- a/tests/libqos/pci-spapr.c
+++ b/tests/libqos/pci-spapr.c
@@ -48,72 +48,36 @@ static uint8_t qpci_spapr_pio_readb(QPCIBus *bus, uint32_t addr)
     return readb(s->pio_cpu_base + addr);
 }
 
-static uint8_t qpci_spapr_mmio32_readb(QPCIBus *bus, uint32_t addr)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    return readb(s->mmio32_cpu_base + addr);
-}
-
 static void qpci_spapr_pio_writeb(QPCIBus *bus, uint32_t addr, uint8_t val)
 {
     QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
     writeb(s->pio_cpu_base + addr, val);
 }
 
-static void qpci_spapr_mmio32_writeb(QPCIBus *bus, uint32_t addr, uint8_t val)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    writeb(s->mmio32_cpu_base + addr, val);
-}
-
 static uint16_t qpci_spapr_pio_readw(QPCIBus *bus, uint32_t addr)
 {
     QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
     return bswap16(readw(s->pio_cpu_base + addr));
 }
 
-static uint16_t qpci_spapr_mmio32_readw(QPCIBus *bus, uint32_t addr)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    return bswap16(readw(s->mmio32_cpu_base + addr));
-}
-
 static void qpci_spapr_pio_writew(QPCIBus *bus, uint32_t addr, uint16_t val)
 {
     QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
     writew(s->pio_cpu_base + addr, bswap16(val));
 }
 
-static void qpci_spapr_mmio32_writew(QPCIBus *bus, uint32_t addr, uint16_t val)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    writew(s->mmio32_cpu_base + addr, bswap16(val));
-}
-
 static uint32_t qpci_spapr_pio_readl(QPCIBus *bus, uint32_t addr)
 {
     QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
     return bswap32(readl(s->pio_cpu_base + addr));
 }
 
-static uint32_t qpci_spapr_mmio32_readl(QPCIBus *bus, uint32_t addr)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    return bswap32(readl(s->mmio32_cpu_base + addr));
-}
-
 static void qpci_spapr_pio_writel(QPCIBus *bus, uint32_t addr, uint32_t val)
 {
     QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
     writel(s->pio_cpu_base + addr, bswap32(val));
 }
 
-static void qpci_spapr_mmio32_writel(QPCIBus *bus, uint32_t addr, uint32_t val)
-{
-    QPCIBusSPAPR *s = container_of(bus, QPCIBusSPAPR, bus);
-    writel(s->mmio32_cpu_base + addr, bswap32(val));
-}
-
 static void qpci_spapr_memread(QPCIBus *bus, uint32_t addr,
                                void *buf, size_t len)
 {
@@ -194,14 +158,6 @@ QPCIBus *qpci_init_spapr(QGuestAllocator *alloc)
     ret->bus.pio_writew = qpci_spapr_pio_writew;
     ret->bus.pio_writel = qpci_spapr_pio_writel;
 
-    ret->bus.mmio_readb = qpci_spapr_mmio32_readb;
-    ret->bus.mmio_readw = qpci_spapr_mmio32_readw;
-    ret->bus.mmio_readl = qpci_spapr_mmio32_readl;
-
-    ret->bus.mmio_writeb = qpci_spapr_mmio32_writeb;
-    ret->bus.mmio_writew = qpci_spapr_mmio32_writew;
-    ret->bus.mmio_writel = qpci_spapr_mmio32_writel;
-
     ret->bus.memread = qpci_spapr_memread;
     ret->bus.memwrite = qpci_spapr_memwrite;
 
diff --git a/tests/libqos/pci.c b/tests/libqos/pci.c
index 146b063..bdffeb3 100644
--- a/tests/libqos/pci.c
+++ b/tests/libqos/pci.c
@@ -230,7 +230,9 @@ uint8_t qpci_io_readb(QPCIDevice *dev, void *data)
     if (addr < QPCI_PIO_LIMIT) {
         return dev->bus->pio_readb(dev->bus, addr);
     } else {
-        return dev->bus->mmio_readb(dev->bus, addr);
+        uint8_t val;
+        dev->bus->memread(dev->bus, addr, &val, sizeof(val));
+        return val;
     }
 }
 
@@ -241,7 +243,9 @@ uint16_t qpci_io_readw(QPCIDevice *dev, void *data)
     if (addr < QPCI_PIO_LIMIT) {
         return dev->bus->pio_readw(dev->bus, addr);
     } else {
-        return dev->bus->mmio_readw(dev->bus, addr);
+        uint16_t val;
+        dev->bus->memread(dev->bus, addr, &val, sizeof(val));
+        return le16_to_cpu(val);
     }
 }
 
@@ -252,7 +256,9 @@ uint32_t qpci_io_readl(QPCIDevice *dev, void *data)
     if (addr < QPCI_PIO_LIMIT) {
         return dev->bus->pio_readl(dev->bus, addr);
     } else {
-        return dev->bus->mmio_readl(dev->bus, addr);
+        uint32_t val;
+        dev->bus->memread(dev->bus, addr, &val, sizeof(val));
+        return le32_to_cpu(val);
     }
 }
 
@@ -263,7 +269,7 @@ void qpci_io_writeb(QPCIDevice *dev, void *data, uint8_t value)
     if (addr < QPCI_PIO_LIMIT) {
         dev->bus->pio_writeb(dev->bus, addr, value);
     } else {
-        dev->bus->mmio_writeb(dev->bus, addr, value);
+        dev->bus->memwrite(dev->bus, addr, &value, sizeof(value));
     }
 }
 
@@ -274,7 +280,8 @@ void qpci_io_writew(QPCIDevice *dev, void *data, uint16_t value)
     if (addr < QPCI_PIO_LIMIT) {
         dev->bus->pio_writew(dev->bus, addr, value);
     } else {
-        dev->bus->mmio_writew(dev->bus, addr, value);
+        value = cpu_to_le16(value);
+        dev->bus->memwrite(dev->bus, addr, &value, sizeof(value));
     }
 }
 
@@ -285,7 +292,8 @@ void qpci_io_writel(QPCIDevice *dev, void *data, uint32_t value)
     if (addr < QPCI_PIO_LIMIT) {
         dev->bus->pio_writel(dev->bus, addr, value);
     } else {
-        dev->bus->mmio_writel(dev->bus, addr, value);
+        value = cpu_to_le32(value);
+        dev->bus->memwrite(dev->bus, addr, &value, sizeof(value));
     }
 }
 
diff --git a/tests/libqos/pci.h b/tests/libqos/pci.h
index 2b08362..ce6ed08 100644
--- a/tests/libqos/pci.h
+++ b/tests/libqos/pci.h
@@ -27,18 +27,10 @@ struct QPCIBus {
     uint16_t (*pio_readw)(QPCIBus *bus, uint32_t addr);
     uint32_t (*pio_readl)(QPCIBus *bus, uint32_t addr);
 
-    uint8_t (*mmio_readb)(QPCIBus *bus, uint32_t addr);
-    uint16_t (*mmio_readw)(QPCIBus *bus, uint32_t addr);
-    uint32_t (*mmio_readl)(QPCIBus *bus, uint32_t addr);
-
     void (*pio_writeb)(QPCIBus *bus, uint32_t addr, uint8_t value);
     void (*pio_writew)(QPCIBus *bus, uint32_t addr, uint16_t value);
     void (*pio_writel)(QPCIBus *bus, uint32_t addr, uint32_t value);
 
-    void (*mmio_writeb)(QPCIBus *bus, uint32_t addr, uint8_t value);
-    void (*mmio_writew)(QPCIBus *bus, uint32_t addr, uint16_t value);
-    void (*mmio_writel)(QPCIBus *bus, uint32_t addr, uint32_t value);
-
     void (*memread)(QPCIBus *bus, uint32_t addr, void *buf, size_t len);
     void (*memwrite)(QPCIBus *bus, uint32_t addr, const void *buf, size_t len);