[Qemu-devel] [PATCH] sparc32: ledma extra registers

[Bob Breuer <breuerr@mc.net>]

ledma has 0x20 bytes of registers according to OBP, and at least Solaris9
reads the 5th register which is beyond what we've mapped.  So let's setup
a flag (inspired by a previous patch from Blue Swirl) to identify ledma
from espdma, and map another 16 bytes of registers which return 0.

Signed-off-by: Bob Breuer <breuerr@mc.net>
---
 hw/sparc32_dma.c |   15 ++++++++++++++-
 hw/sun4m.c       |   16 +++++++++-------
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/hw/sparc32_dma.c b/hw/sparc32_dma.c
index e78f025..56be8c8 100644
--- a/hw/sparc32_dma.c
+++ b/hw/sparc32_dma.c
@@ -44,6 +44,9 @@
 /* We need the mask, because one instance of the device is not page
    aligned (ledma, start address 0x0010) */
 #define DMA_MASK (DMA_SIZE - 1)
+/* ledma has more than 4 registers, Solaris reads the 5th one */
+#define DMA_ETH_SIZE (8 * sizeof(uint32_t))
+#define DMA_MAX_REG_OFFSET (2 * DMA_SIZE - 1)
 
 #define DMA_VER 0xa0000000
 #define DMA_INTR 1
@@ -65,6 +68,7 @@ struct DMAState {
     qemu_irq irq;
     void *iommu;
     qemu_irq gpio[2];
+    uint32_t is_ledma;
 };
 
 enum {
@@ -165,6 +169,9 @@ static uint32_t dma_mem_readl(void *opaque, target_phys_addr_t addr)
     DMAState *s = opaque;
     uint32_t saddr;
 
+    if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
+        return 0; /* extra mystery register(s) */
+    }
     saddr = (addr & DMA_MASK) >> 2;
     trace_sparc32_dma_mem_readl(addr, s->dmaregs[saddr]);
     return s->dmaregs[saddr];
@@ -175,6 +182,9 @@ static void dma_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)
     DMAState *s = opaque;
     uint32_t saddr;
 
+    if (s->is_ledma && (addr > DMA_MAX_REG_OFFSET)) {
+        return; /* extra mystery register(s) */
+    }
     saddr = (addr & DMA_MASK) >> 2;
     trace_sparc32_dma_mem_writel(addr, s->dmaregs[saddr], val);
     switch (saddr) {
@@ -254,12 +264,14 @@ static int sparc32_dma_init1(SysBusDevice *dev)
 {
     DMAState *s = FROM_SYSBUS(DMAState, dev);
     int dma_io_memory;
+    int reg_size;
 
     sysbus_init_irq(dev, &s->irq);
 
     dma_io_memory = cpu_register_io_memory(dma_mem_read, dma_mem_write, s,
                                            DEVICE_NATIVE_ENDIAN);
-    sysbus_init_mmio(dev, DMA_SIZE, dma_io_memory);
+    reg_size = s->is_ledma ? DMA_ETH_SIZE : DMA_SIZE;
+    sysbus_init_mmio(dev, reg_size, dma_io_memory);
 
     qdev_init_gpio_in(&dev->qdev, dma_set_irq, 1);
     qdev_init_gpio_out(&dev->qdev, s->gpio, 2);
@@ -275,6 +287,7 @@ static SysBusDeviceInfo sparc32_dma_info = {
     .qdev.reset = dma_reset,
     .qdev.props = (Property[]) {
         DEFINE_PROP_PTR("iommu_opaque", DMAState, iommu),
+        DEFINE_PROP_UINT32("is_ledma", DMAState, is_ledma, 0),
         DEFINE_PROP_END_OF_LIST(),
     }
 };
diff --git a/hw/sun4m.c b/hw/sun4m.c
index 4795b3f..30e8a21 100644
--- a/hw/sun4m.c
+++ b/hw/sun4m.c
@@ -378,13 +378,14 @@ static void *iommu_init(target_phys_addr_t addr, uint32_t version, qemu_irq irq)
 }
 
 static void *sparc32_dma_init(target_phys_addr_t daddr, qemu_irq parent_irq,
-                              void *iommu, qemu_irq *dev_irq)
+                              void *iommu, qemu_irq *dev_irq, int is_ledma)
 {
     DeviceState *dev;
     SysBusDevice *s;
 
     dev = qdev_create(NULL, "sparc32_dma");
     qdev_prop_set_ptr(dev, "iommu_opaque", iommu);
+    qdev_prop_set_uint32(dev, "is_ledma", is_ledma);
     qdev_init_nofail(dev);
     s = sysbus_from_qdev(dev);
     sysbus_connect_irq(s, 0, parent_irq);
@@ -862,10 +863,10 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef, ram_addr_t RAM_size,
     }
 
     espdma = sparc32_dma_init(hwdef->dma_base, slavio_irq[18],
-                              iommu, &espdma_irq);
+                              iommu, &espdma_irq, 0);
 
     ledma = sparc32_dma_init(hwdef->dma_base + 16ULL,
-                             slavio_irq[16], iommu, &ledma_irq);
+                             slavio_irq[16], iommu, &ledma_irq, 1);
 
     if (graphic_depth != 8 && graphic_depth != 24) {
         fprintf(stderr, "qemu: Unsupported depth: %d\n", graphic_depth);
@@ -1524,10 +1525,11 @@ static void sun4d_hw_init(const struct sun4d_hwdef *hwdef, ram_addr_t RAM_size,
                                     sbi_irq[0]);
 
     espdma = sparc32_dma_init(hwdef->espdma_base, sbi_irq[3],
-                              iounits[0], &espdma_irq);
+                              iounits[0], &espdma_irq, 0);
 
+    /* should be lebuffer instead */
     ledma = sparc32_dma_init(hwdef->ledma_base, sbi_irq[4],
-                             iounits[0], &ledma_irq);
+                             iounits[0], &ledma_irq, 0);
 
     if (graphic_depth != 8 && graphic_depth != 24) {
         fprintf(stderr, "qemu: Unsupported depth: %d\n", graphic_depth);
@@ -1707,10 +1709,10 @@ static void sun4c_hw_init(const struct sun4c_hwdef *hwdef, ram_addr_t RAM_size,
                        slavio_irq[1]);
 
     espdma = sparc32_dma_init(hwdef->dma_base, slavio_irq[2],
-                              iommu, &espdma_irq);
+                              iommu, &espdma_irq, 0);
 
     ledma = sparc32_dma_init(hwdef->dma_base + 16ULL,
-                             slavio_irq[3], iommu, &ledma_irq);
+                             slavio_irq[3], iommu, &ledma_irq, 1);
 
     if (graphic_depth != 8 && graphic_depth != 24) {
         fprintf(stderr, "qemu: Unsupported depth: %d\n", graphic_depth);