With all MPIPL support in place, export a "dump" node in device tree,
signifying that PowerNV QEMU platform supports MPIPL

Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
---
 hw/ppc/pnv.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index 7c36f3a00e90..8a62b0ee1074 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -54,6 +54,7 @@
 #include "hw/ppc/pnv_chip.h"
 #include "hw/ppc/pnv_xscom.h"
 #include "hw/ppc/pnv_pnor.h"
+#include "hw/ppc/pnv_mpipl.h"
 
 #include "hw/isa/isa.h"
 #include "hw/char/serial-isa.h"
@@ -671,6 +672,39 @@ static void pnv_dt_power_mgt(PnvMachineState *pnv, void *fdt)
     _FDT(fdt_setprop_cell(fdt, off, "ibm,enabled-stop-levels", 0xc0000000));
 }
 
+static void pnv_dt_mpipl_dump(PnvMachineState *pnv, void *fdt)
+{
+    int off;
+
+    /*
+     * Add "dump" node so kernel knows MPIPL (aka fadump) is supported
+     *
+     * Note: This is only needed to be done since we are passing device tree to
+     * opal
+     *
+     * In case HDAT is supported in future, then opal can add these nodes by
+     * itself based on system attribute having MPIPL_SUPPORTED bit set
+     */
+    off = fdt_add_subnode(fdt, 0, "ibm,opal");
+    if (off == -FDT_ERR_EXISTS) {
+        off = fdt_path_offset(fdt, "/ibm,opal");
+    }
+
+    _FDT(off);
+    off = fdt_add_subnode(fdt, off, "dump");
+    _FDT(off);
+    _FDT((fdt_setprop_string(fdt, off, "compatible", "ibm,opal-dump")));
+
+    /* Add kernel and initrd as fw-load-area */
+    uint64_t fw_load_area[4] = {
+        cpu_to_be64(KERNEL_LOAD_ADDR), cpu_to_be64(KERNEL_MAX_SIZE),
+        cpu_to_be64(INITRD_LOAD_ADDR), cpu_to_be64(INITRD_MAX_SIZE)
+    };
+
+    _FDT((fdt_setprop(fdt, off, "fw-load-area",
+                    fw_load_area, sizeof(fw_load_area))));
+}
+
 static void *pnv_dt_create(MachineState *machine)
 {
     PnvMachineClass *pmc = PNV_MACHINE_GET_CLASS(machine);
@@ -733,6 +767,9 @@ static void *pnv_dt_create(MachineState *machine)
         pmc->dt_power_mgt(pnv, fdt);
     }
 
+    /* Advertise support for MPIPL */
+    pnv_dt_mpipl_dump(pnv, fdt);
+
     return fdt;
 }
 
-- 
2.52.0

On 06/12/25 11:26 am, Aditya Gupta wrote:
> With all MPIPL support in place, export a "dump" node in device tree,
> signifying that PowerNV QEMU platform supports MPIPL
> 
> Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
> ---
>   hw/ppc/pnv.c | 37 +++++++++++++++++++++++++++++++++++++
>   1 file changed, 37 insertions(+)
> 
> diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
> index 7c36f3a00e90..8a62b0ee1074 100644
> --- a/hw/ppc/pnv.c
> +++ b/hw/ppc/pnv.c
> @@ -54,6 +54,7 @@
>   #include "hw/ppc/pnv_chip.h"
>   #include "hw/ppc/pnv_xscom.h"
>   #include "hw/ppc/pnv_pnor.h"
> +#include "hw/ppc/pnv_mpipl.h"
>   
>   #include "hw/isa/isa.h"
>   #include "hw/char/serial-isa.h"
> @@ -671,6 +672,39 @@ static void pnv_dt_power_mgt(PnvMachineState *pnv, void *fdt)
>       _FDT(fdt_setprop_cell(fdt, off, "ibm,enabled-stop-levels", 0xc0000000));
>   }
>   
> +static void pnv_dt_mpipl_dump(PnvMachineState *pnv, void *fdt)
> +{
> +    int off;
> +
> +    /*
> +     * Add "dump" node so kernel knows MPIPL (aka fadump) is supported
> +     *
> +     * Note: This is only needed to be done since we are passing device tree to
> +     * opal
> +     *
> +     * In case HDAT is supported in future, then opal can add these nodes by
> +     * itself based on system attribute having MPIPL_SUPPORTED bit set
> +     */
> +    off = fdt_add_subnode(fdt, 0, "ibm,opal");
> +    if (off == -FDT_ERR_EXISTS) {
> +        off = fdt_path_offset(fdt, "/ibm,opal");
> +    }
> +
> +    _FDT(off);
> +    off = fdt_add_subnode(fdt, off, "dump");
> +    _FDT(off);
> +    _FDT((fdt_setprop_string(fdt, off, "compatible", "ibm,opal-dump")));
> +

> +    /* Add kernel and initrd as fw-load-area */
> +    uint64_t fw_load_area[4] = {
> +        cpu_to_be64(KERNEL_LOAD_ADDR), cpu_to_be64(KERNEL_MAX_SIZE),
> +        cpu_to_be64(INITRD_LOAD_ADDR), cpu_to_be64(INITRD_MAX_SIZE)
> +    };
> +
> +    _FDT((fdt_setprop(fdt, off, "fw-load-area",
> +                    fw_load_area, sizeof(fw_load_area))));
> +}
> +

While the changelog only talks about dump node, fw-load-area is
exported too. A comment explaining what and why it is used helps..

- Hari