This memory range is used to transfer data between ACPI in guest and Qemu,
it occupies two pages:
- one is RAM-based used to save the input info of _DSM method and Qemu reuse
it store output info
- another one is MMIO-based, ACPI write data to this page to transfer the
control to Qemu
Signed-off-by: Xiao Guangrong <guangrong.x...@linux.intel.com>
---
hw/mem/pc-nvdimm.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 79 insertions(+), 1 deletion(-)
diff --git a/hw/mem/pc-nvdimm.c b/hw/mem/pc-nvdimm.c
index e7cff29..4c290cb 100644
--- a/hw/mem/pc-nvdimm.c
+++ b/hw/mem/pc-nvdimm.c
@@ -37,6 +37,10 @@
static struct nvdimms_info {
ram_addr_t current_addr;
+
+ ram_addr_t dsm_addr;
+ int dsm_size;
+
int device_index;
} nvdimms_info;
@@ -324,14 +328,88 @@ static void build_nfit_table(GSList *device_list, char
*buf)
}
}
+struct dsm_buffer {
+ /* RAM page. */
+ uint32_t handle;
+ uint8_t arg0[16];
+ uint32_t arg1;
+ uint32_t arg2;
+ union {
+ char arg3[PAGE_SIZE - 3 * sizeof(uint32_t) - 16 * sizeof(uint8_t)];
+ };
+
+ /* MMIO page. */
+ union {
+ uint32_t notify;
+ char pedding[PAGE_SIZE];
+ };
+};
+
+static uint64_t dsm_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ return 0;
+}
+
+static void dsm_write(void *opaque, hwaddr addr,
+ uint64_t val, unsigned size)
+{
+}
+
+static const MemoryRegionOps dsm_ops = {
+ .read = dsm_read,
+ .write = dsm_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static int build_dsm_buffer(void)
+{
+ MemoryRegion *dsm_ram_mr, *dsm_mmio_mr;
+ ram_addr_t addr;;
+
+ QEMU_BUILD_BUG_ON(PAGE_SIZE * 2 != sizeof(struct dsm_buffer));
+
+ /* DSM buffer has already been built. */
+ if (nvdimms_info.dsm_addr) {
+ return 0;
+ }
+
+ addr = reserved_range_push(2 * PAGE_SIZE);
+ if (!addr) {
+ return -1;
+ }
+
+ nvdimms_info.dsm_addr = addr;
+ nvdimms_info.dsm_size = PAGE_SIZE * 2;
+
+ dsm_ram_mr = g_new(MemoryRegion, 1);
+ memory_region_init_ram(dsm_ram_mr, NULL, "dsm_ram", PAGE_SIZE,
+ &error_abort);
+ vmstate_register_ram_global(dsm_ram_mr);
+ memory_region_add_subregion(get_system_memory(), addr, dsm_ram_mr);
+
+ dsm_mmio_mr = g_new(MemoryRegion, 1);
+ memory_region_init_io(dsm_mmio_mr, NULL, &dsm_ops, dsm_ram_mr,
+ "dsm_mmio", PAGE_SIZE);
+ memory_region_add_subregion(get_system_memory(), addr + PAGE_SIZE,
+ dsm_mmio_mr);
+ return 0;
+}
+
void pc_nvdimm_build_nfit_table(GArray *table_offsets, GArray *table_data,
GArray *linker)
{
- GSList *list = get_nvdimm_built_list();
+ GSList *list;
size_t total;
char *buf;
int nfit_start, nr;
+ if (build_dsm_buffer()) {
+ fprintf(stderr, "do not have enough space for DSM buffer.\n");
+ return;
+ }
+
+ list = get_nvdimm_built_list();
nr = get_nvdimm_device_number(list);
total = get_nfit_total_size(nr);
--
2.1.0
