hw/misc/aspeed_xdma: New device

The XDMA engine embedded in the Aspeed SOCs performs PCI DMA operations
between the SOC (acting as a BMC) and a host processor in a server.

The XDMA engine exists on the AST2400, AST2500, and AST2600 SOCs, so
enable it for all of those. Add trace events on the important register
writes in the XDMA engine.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20190618165311.27066-21-clg@kaod.org
[clg: - changed title ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 165 insertions, 0 deletions

diff --git a/hw/misc/aspeed_xdma.c b/hw/misc/aspeed_xdma.c
new file mode 100644
index 0000000000..eebd4ad540
--- /dev/null
+++ b/hw/misc/aspeed_xdma.c
@@ -0,0 +1,165 @@
+/*
+ * ASPEED XDMA Controller
+ * Eddie James <eajames@linux.ibm.com>
+ *
+ * Copyright (C) 2019 IBM Corp
+ * SPDX-License-Identifer: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+#include "hw/misc/aspeed_xdma.h"
+#include "qapi/error.h"
+
+#include "trace.h"
+
+#define XDMA_BMC_CMDQ_ADDR         0x10
+#define XDMA_BMC_CMDQ_ENDP         0x14
+#define XDMA_BMC_CMDQ_WRP          0x18
+#define  XDMA_BMC_CMDQ_W_MASK      0x0003FFFF
+#define XDMA_BMC_CMDQ_RDP          0x1C
+#define  XDMA_BMC_CMDQ_RDP_MAGIC   0xEE882266
+#define XDMA_IRQ_ENG_CTRL          0x20
+#define  XDMA_IRQ_ENG_CTRL_US_COMP BIT(4)
+#define  XDMA_IRQ_ENG_CTRL_DS_COMP BIT(5)
+#define  XDMA_IRQ_ENG_CTRL_W_MASK  0xBFEFF07F
+#define XDMA_IRQ_ENG_STAT          0x24
+#define  XDMA_IRQ_ENG_STAT_US_COMP BIT(4)
+#define  XDMA_IRQ_ENG_STAT_DS_COMP BIT(5)
+#define  XDMA_IRQ_ENG_STAT_RESET   0xF8000000
+#define XDMA_MEM_SIZE              0x1000
+
+#define TO_REG(addr) ((addr) / sizeof(uint32_t))
+
+static uint64_t aspeed_xdma_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    uint32_t val = 0;
+    AspeedXDMAState *xdma = opaque;
+
+    if (addr < ASPEED_XDMA_REG_SIZE) {
+        val = xdma->regs[TO_REG(addr)];
+    }
+
+    return (uint64_t)val;
+}
+
+static void aspeed_xdma_write(void *opaque, hwaddr addr, uint64_t val,
+                              unsigned int size)
+{
+    unsigned int idx;
+    uint32_t val32 = (uint32_t)val;
+    AspeedXDMAState *xdma = opaque;
+
+    if (addr >= ASPEED_XDMA_REG_SIZE) {
+        return;
+    }
+
+    switch (addr) {
+    case XDMA_BMC_CMDQ_ENDP:
+        xdma->regs[TO_REG(addr)] = val32 & XDMA_BMC_CMDQ_W_MASK;
+        break;
+    case XDMA_BMC_CMDQ_WRP:
+        idx = TO_REG(addr);
+        xdma->regs[idx] = val32 & XDMA_BMC_CMDQ_W_MASK;
+        xdma->regs[TO_REG(XDMA_BMC_CMDQ_RDP)] = xdma->regs[idx];
+
+        trace_aspeed_xdma_write(addr, val);
+
+        if (xdma->bmc_cmdq_readp_set) {
+            xdma->bmc_cmdq_readp_set = 0;
+        } else {
+            xdma->regs[TO_REG(XDMA_IRQ_ENG_STAT)] |=
+                XDMA_IRQ_ENG_STAT_US_COMP | XDMA_IRQ_ENG_STAT_DS_COMP;
+
+            if (xdma->regs[TO_REG(XDMA_IRQ_ENG_CTRL)] &
+                (XDMA_IRQ_ENG_CTRL_US_COMP | XDMA_IRQ_ENG_CTRL_DS_COMP))
+                qemu_irq_raise(xdma->irq);
+        }
+        break;
+    case XDMA_BMC_CMDQ_RDP:
+        trace_aspeed_xdma_write(addr, val);
+
+        if (val32 == XDMA_BMC_CMDQ_RDP_MAGIC) {
+            xdma->bmc_cmdq_readp_set = 1;
+        }
+        break;
+    case XDMA_IRQ_ENG_CTRL:
+        xdma->regs[TO_REG(addr)] = val32 & XDMA_IRQ_ENG_CTRL_W_MASK;
+        break;
+    case XDMA_IRQ_ENG_STAT:
+        trace_aspeed_xdma_write(addr, val);
+
+        idx = TO_REG(addr);
+        if (val32 & (XDMA_IRQ_ENG_STAT_US_COMP | XDMA_IRQ_ENG_STAT_DS_COMP)) {
+            xdma->regs[idx] &=
+                ~(XDMA_IRQ_ENG_STAT_US_COMP | XDMA_IRQ_ENG_STAT_DS_COMP);
+            qemu_irq_lower(xdma->irq);
+        }
+        break;
+    default:
+        xdma->regs[TO_REG(addr)] = val32;
+        break;
+    }
+}
+
+static const MemoryRegionOps aspeed_xdma_ops = {
+    .read = aspeed_xdma_read,
+    .write = aspeed_xdma_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid.min_access_size = 4,
+    .valid.max_access_size = 4,
+};
+
+static void aspeed_xdma_realize(DeviceState *dev, Error **errp)
+{
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+    AspeedXDMAState *xdma = ASPEED_XDMA(dev);
+
+    sysbus_init_irq(sbd, &xdma->irq);
+    memory_region_init_io(&xdma->iomem, OBJECT(xdma), &aspeed_xdma_ops, xdma,
+                          TYPE_ASPEED_XDMA, XDMA_MEM_SIZE);
+    sysbus_init_mmio(sbd, &xdma->iomem);
+}
+
+static void aspeed_xdma_reset(DeviceState *dev)
+{
+    AspeedXDMAState *xdma = ASPEED_XDMA(dev);
+
+    xdma->bmc_cmdq_readp_set = 0;
+    memset(xdma->regs, 0, ASPEED_XDMA_REG_SIZE);
+    xdma->regs[TO_REG(XDMA_IRQ_ENG_STAT)] = XDMA_IRQ_ENG_STAT_RESET;
+
+    qemu_irq_lower(xdma->irq);
+}
+
+static const VMStateDescription aspeed_xdma_vmstate = {
+    .name = TYPE_ASPEED_XDMA,
+    .version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, AspeedXDMAState, ASPEED_XDMA_NUM_REGS),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static void aspeed_xdma_class_init(ObjectClass *classp, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(classp);
+
+    dc->realize = aspeed_xdma_realize;
+    dc->reset = aspeed_xdma_reset;
+    dc->vmsd = &aspeed_xdma_vmstate;
+}
+
+static const TypeInfo aspeed_xdma_info = {
+    .name          = TYPE_ASPEED_XDMA,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AspeedXDMAState),
+    .class_init    = aspeed_xdma_class_init,
+};
+
+static void aspeed_xdma_register_type(void)
+{
+    type_register_static(&aspeed_xdma_info);
+}
+type_init(aspeed_xdma_register_type);