- implements QEMU hardware part of memory hotplug protocol
described at "docs/specs/acpi_mem_hotplug.txt"
- handles only memory add notification event for now
Signed-off-by: Igor Mammedov <imamm...@redhat.com>
---
docs/specs/acpi_mem_hotplug.txt | 38 ++++++++++
hw/acpi/core.c | 144 +++++++++++++++++++++++++++++++++++++++
include/hw/acpi/acpi.h | 24 +++++++
3 files changed, 206 insertions(+), 0 deletions(-)
create mode 100644 docs/specs/acpi_mem_hotplug.txt
diff --git a/docs/specs/acpi_mem_hotplug.txt b/docs/specs/acpi_mem_hotplug.txt
new file mode 100644
index 0000000..fc34142
--- /dev/null
+++ b/docs/specs/acpi_mem_hotplug.txt
@@ -0,0 +1,38 @@
+QEMU<->ACPI BIOS memory hotplug interface
+--------------------------------------
+
+ACPI BIOS GPE.3 handler is dedicated for notifying OS about memory hot-add
+or hot-remove events.
+
+Memory hot-plug interface (IO port 0xa00-0xa17, 1-4 byte access):
+---------------------------------------------------------------
+0xa00:
+ read access:
+ [0x0-0x3] Lo part of memory device phys address
+ [0x4-0x7] Hi part of memory device phys address
+ [0x8-0xb] Lo part of memory device size in bytes
+ [0xc-0xf] Hi part of memory device size in bytes
+ [0x14] highest memory hot-plug interface version supported by QEMU
+ [0x15] Memory device status fields
+ bits:
+ 1: device is enabled and may be used by guest
+ 2: device insert event, used by ACPI BIOS to distinguish
+ device for which no device check event to OSPM was issued
+ [0x16-0x17] reserved
+
+ write access:
+ [0x0-0x3] Memory device slot selector, selects active memory device.
+ All following accesses to other registers in 0xaf80-0xaf97
+ region will read/store data from/to selected memory device.
+ [0x4-0x7] OST event code reported by OSPM
+ [0x8-0xb] OST status code reported by OSPM
+ [0x15] Memory device status fields
+ bits:
+ 2: if set to 1 clears device insert event, set by ACPI BIOS
+ after it has sent device check event to OSPM for
+ seleted memory device
+
+Selecting memory device slot beyond present range has no effect on platform:
+ - not documented above write accesses to memory hot-plug registers
+ are ignored;
+ - not documented above read accesses to memory hot-plug registers return
0xFF
diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 8c0d48c..18e169c 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -680,3 +680,147 @@ void acpi_update_sci(ACPIREGS *regs, qemu_irq irq,
uint32_t gpe0_sts_mask)
(regs->pm1.evt.en & ACPI_BITMASK_TIMER_ENABLE) &&
!(pm1a_sts & ACPI_BITMASK_TIMER_STATUS));
}
+
+static uint64_t acpi_memory_hotplug_read(void *opaque, hwaddr addr,
+ unsigned int size)
+{
+ uint32_t val = 0;
+ MemHotplugState *mem_st = opaque;
+ MemStatus *mdev;
+
+ if (mem_st->selector >= mem_st->dev_count) {
+ return 0;
+ }
+
+ mdev = &mem_st->devs[mem_st->selector];
+ switch (addr) {
+ case 0x0: /* Lo part of phys address where DIMM is mapped */
+ val = object_property_get_int(OBJECT(mdev->dimm), "start", NULL);
+ break;
+ case 0x4: /* Hi part of phys address where DIMM is mapped */
+ val = object_property_get_int(OBJECT(mdev->dimm), "start", NULL) >> 32;
+ break;
+ case 0x8: /* Lo part of DIMM size */
+ val = object_property_get_int(OBJECT(mdev->dimm), "size", NULL);
+ break;
+ case 0xc: /* Hi part of DIMM size */
+ val = object_property_get_int(OBJECT(mdev->dimm), "size", NULL) >> 32;
+ break;
+ case 0x10: /* node proximity for _PXM method */
+ val = object_property_get_int(OBJECT(mdev->dimm), "node", NULL);
+ break;
+ case 0x14: /* intf version */
+ val = 1;
+ break;
+ case 0x15: /* pack and return is_* fields */
+ val |= mdev->is_enabled ? 1 : 0;
+ val |= mdev->is_inserting ? 2 : 0;
+ break;
+ }
+ return val;
+}
+
+static void acpi_memory_hotplug_write(void *opaque, hwaddr addr, uint64_t data,
+ unsigned int size)
+{
+ MemHotplugState *mem_st = opaque;
+ MemStatus *mdev;
+
+ if (!mem_st->dev_count) {
+ return;
+ }
+
+ if (addr) {
+ if (mem_st->selector >= mem_st->dev_count) {
+ return;
+ }
+ }
+
+ switch (addr) {
+ case 0x0: /* DIMM slot selector */
+ mem_st->selector = data;
+ break;
+ case 0x4: /* _OST event */
+ mdev = &mem_st->devs[mem_st->selector];
+ if (data == 1) {
+ /* TODO: handle device insert OST event */
+ } else if (data == 3) {
+ /* TODO: handle device remove OST event */
+ }
+ mdev->ost_event = data;
+ break;
+ case 0x8: /* _OST status */
+ mdev = &mem_st->devs[mem_st->selector];
+ mdev->ost_status = data;
+ /* TODO: report async error */
+ /* TODO: implement memory removal on guest signal */
+ break;
+ case 0x15:
+ mdev = &mem_st->devs[mem_st->selector];
+ if (data & 2) { /* clear insert event */
+ mdev->is_inserting = false;
+ }
+ break;
+ }
+
+}
+static const MemoryRegionOps acpi_memory_hotplug_ops = {
+ .read = acpi_memory_hotplug_read,
+ .write = acpi_memory_hotplug_write,
+ .endianness = DEVICE_LITTLE_ENDIAN,
+ .valid = {
+ .min_access_size = 1,
+ .max_access_size = 4,
+ },
+};
+
+void acpi_memory_hotplug_init(Object *owner, MemoryRegion *io,
+ MemHotplugState *state)
+{
+ QemuOpts *opts = qemu_opts_find(qemu_find_opts("memory-opts"), NULL);
+ g_assert(opts);
+
+ state->dev_count = qemu_opt_get_number(opts, "slots", 0);
+
+ if (!state->dev_count) {
+ return;
+ }
+
+ state->devs = g_malloc0(sizeof(*state->devs) * state->dev_count);
+ memory_region_init_io(io, owner, &acpi_memory_hotplug_ops, state,
+ "apci-mem-hotplug", ACPI_MEMORY_HOTPLUG_IO_LEN);
+}
+
+int acpi_memory_hotplug_cb(ACPIREGS *regs, MemHotplugState *mem_st,
+ DeviceState *dev, HotplugState state)
+{
+ MemStatus *mdev;
+ Error *local_err = NULL;
+ int slot = object_property_get_int(OBJECT(dev), "slot", &local_err);
+
+ if (error_is_set(&local_err)) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ return -1;
+ }
+
+ if (slot >= mem_st->dev_count) {
+ char *dev_path = object_get_canonical_path(OBJECT(dev));
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "acpi_memory_hotplug_cb: "
+ "device [%s] returned invalid memory slot[%d]",
+ dev_path, slot);
+ g_free(dev_path);
+ return -1;
+ }
+
+ mdev = &mem_st->devs[slot];
+ if (state == HOTPLUG_ENABLED) {
+ mdev->dimm = dev;
+ mdev->is_enabled = true;
+ mdev->is_inserting = true;
+ }
+
+ /* do ACPI magic */
+ regs->gpe.sts[0] |= ACPI_MEMORY_HOTPLUG_STATUS;
+ return 0;
+}
diff --git a/include/hw/acpi/acpi.h b/include/hw/acpi/acpi.h
index c4ae7d7..e5717df 100644
--- a/include/hw/acpi/acpi.h
+++ b/include/hw/acpi/acpi.h
@@ -168,6 +168,30 @@ uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t
addr);
void acpi_update_sci(ACPIREGS *acpi_regs, qemu_irq irq, uint32_t
gpe0_sts_mask);
+#define ACPI_MEMORY_HOTPLUG_IO_LEN 24
+#define ACPI_MEMORY_HOTPLUG_BASE 0x0a00
+
+#define ACPI_MEMORY_HOTPLUG_STATUS 8
+
+typedef struct MemStatus {
+ DeviceState *dimm;
+ bool is_enabled;
+ bool is_inserting;
+ uint32_t ost_event;
+ uint32_t ost_status;
+} MemStatus;
+
+typedef struct MemHotplugState {
+ uint32_t selector;
+ uint32_t dev_count;
+ MemStatus *devs;
+} MemHotplugState;
+
+void acpi_memory_hotplug_init(Object *owner, MemoryRegion *io,
+ MemHotplugState *state);
+
+int acpi_memory_hotplug_cb(ACPIREGS *regs, MemHotplugState *mem_st,
+ DeviceState *dev, HotplugState state);
/* acpi.c */
extern int acpi_enabled;
extern char unsigned *acpi_tables;
--
1.7.1
