Re: [Qemu-arm] [Qemu-devel] [PATCH v6 12/18] hw/arm/boot: Expose the PC-DIMM nodes in the DT

[Auger Eric]

Hi Igor,

On 2/18/19 9:58 AM, Igor Mammedov wrote:
> On Tue,  5 Feb 2019 18:33:00 +0100
> Eric Auger <address@hidden> wrote:
> 
>> From: Shameer Kolothum <address@hidden>
>>
>> This patch add memory nodes corresponding to PC-DIMM regions.
> s/add/adds/ or s/This patch add/Add/
> 
>>
>> NV_DIMM and ACPI_NVDIMM configs are not yet set for ARM so we
>> don't need to care about NV-DIMM at this stage.
>>
>> Signed-off-by: Shameer Kolothum <address@hidden>
>> Signed-off-by: Eric Auger <address@hidden>
>>
>> ---
>> v3 -> v4:
>> - git rid of @base and @len in fdt_add_hotpluggable_memory_nodes
>>
>> v1 -> v2:
>> - added qapi_free_MemoryDeviceInfoList and simplify the loop
>> ---
>>  hw/arm/boot.c | 35 +++++++++++++++++++++++++++++++++++
>>  1 file changed, 35 insertions(+)
>>
>> diff --git a/hw/arm/boot.c b/hw/arm/boot.c
>> index 2ef367e15b..2a70e8aa82 100644
>> --- a/hw/arm/boot.c
>> +++ b/hw/arm/boot.c
>> @@ -19,6 +19,7 @@
>>  #include "sysemu/numa.h"
>>  #include "hw/boards.h"
>>  #include "hw/loader.h"
>> +#include "hw/mem/memory-device.h"
>>  #include "elf.h"
>>  #include "sysemu/device_tree.h"
>>  #include "qemu/config-file.h"
>> @@ -526,6 +527,34 @@ static void fdt_add_psci_node(void *fdt)
>>      qemu_fdt_setprop_cell(fdt, "/psci", "migrate", migrate_fn);
>>  }
>>  
>> +static int fdt_add_hotpluggable_memory_nodes(void *fdt,
>> +                                             uint32_t acells, uint32_t 
>> scells) {
>> +    MemoryDeviceInfoList *info, *info_list = qmp_memory_device_list();
>> +    MemoryDeviceInfo *mi;
>> +    PCDIMMDeviceInfo *di;
>> +    bool is_nvdimm;
>> +    int ret = 0;
>> +
>> +    for (info = info_list; info != NULL; info = info->next) {
>> +        mi = info->value;
>> +        is_nvdimm = (mi->type == MEMORY_DEVICE_INFO_KIND_NVDIMM);
>> +        di = !is_nvdimm ? mi->u.dimm.data : mi->u.nvdimm.data;
>> +
>> +        if (is_nvdimm) {
>> +            ret = -ENOENT; /* NV-DIMM not yet supported */
>> +        } else {
>> +            ret = fdt_add_memory_node(fdt, acells, di->addr,
>> +                                      scells, di->size, di->node);
>> +        }
>> +        if (ret < 0) {
>> +            goto out;
>> +        }
>> +    }
>> +out:
>> +    qapi_free_MemoryDeviceInfoList(info_list);
>> +    return ret;
>> +}
>> +
>>  int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
>>                   hwaddr addr_limit, AddressSpace *as)
>>  {
>> @@ -621,6 +650,12 @@ int arm_load_dtb(hwaddr addr, const struct 
>> arm_boot_info *binfo,
>>          }
>>      }
>>  
>> +    rc = fdt_add_hotpluggable_memory_nodes(fdt, acells, scells);
>> +    if (rc < 0) {
>> +            fprintf(stderr, "couldn't add hotpluggable memory nodes\n");
> error message is rather vague, user using nvdimms + pc-dimms on CLI won't have
> a clue that the former is not supported.
> Suggest pass in error_fatal as argument and report more specific error from
> fdt_add_hotpluggable_memory_nodes()
> 
> does this run on reboot?

Yes after a QMP system_reset I can see the DIMMS on guest in /proc/meminfo

Thanks

Eric
> 
>> +            goto fail;
>> +    }
>> +
>>      rc = fdt_path_offset(fdt, "/chosen");
>>      if (rc < 0) {
>>          qemu_fdt_add_subnode(fdt, "/chosen");
>