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[RFC,v1,05/13] spapr: Support ibm, lrdr-capacity device tree property

Message ID 1420697420-16053-6-git-send-email-bharata@linux.vnet.ibm.com
State New
Headers show

Commit Message

Bharata B Rao Jan. 8, 2015, 6:10 a.m. UTC 
Add support for ibm,lrdr-capacity since this is needed by the guest
kernel to know about the possible hot-pluggable CPUs and Memory.

Define minimum hotpluggable memory size as 256MB and start storing maximum
possible memory for the guest in sPAPREnvironment.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
---
 hw/ppc/spapr.c         |  3 ++-
 hw/ppc/spapr_rtas.c    | 28 ++++++++++++++++++++++++++--
 include/hw/ppc/spapr.h |  6 ++++--
 3 files changed, 32 insertions(+), 5 deletions(-)

Comments

Michael Roth Jan. 22, 2015, 9:55 p.m. UTC | #1 
Quoting Bharata B Rao (2015-01-08 00:10:12)
> Add support for ibm,lrdr-capacity since this is needed by the guest
> kernel to know about the possible hot-pluggable CPUs and Memory.
> 
> Define minimum hotpluggable memory size as 256MB and start storing maximum
> possible memory for the guest in sPAPREnvironment.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> ---
>  hw/ppc/spapr.c         |  3 ++-
>  hw/ppc/spapr_rtas.c    | 28 ++++++++++++++++++++++++++--
>  include/hw/ppc/spapr.h |  6 ++++--
>  3 files changed, 32 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index f49b0fa..515d770 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -775,7 +775,7 @@ static void spapr_finalize_fdt(sPAPREnvironment *spapr,
>      }
> 
>      /* RTAS */
> -    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size);
> +    ret = spapr_rtas_device_tree_setup(spapr, fdt, rtas_addr, rtas_size);
>      if (ret < 0) {
>          fprintf(stderr, "Couldn't set up RTAS device tree properties\n");
>      }
> @@ -1473,6 +1473,7 @@ static void ppc_spapr_init(MachineState *machine)
> 
>      /* allocate RAM */
>      spapr->ram_limit = ram_size;
> +    spapr->maxram_limit = machine->maxram_size;
>      memory_region_allocate_system_memory(ram, NULL, "ppc_spapr.ram",
>                                           spapr->ram_limit);
>      memory_region_add_subregion(sysmem, 0, ram);
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index d847f45..e8a0f21 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -29,6 +29,7 @@
>  #include "sysemu/char.h"
>  #include "hw/qdev.h"
>  #include "sysemu/device_tree.h"
> +#include "sysemu/cpus.h"
> 
>  #include "hw/ppc/spapr.h"
>  #include "hw/ppc/spapr_vio.h"
> @@ -551,11 +552,12 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn)
>      rtas_table[token].fn = fn;
>  }
> 
> -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> -                                 hwaddr rtas_size)
> +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> +                                 hwaddr rtas_addr, hwaddr rtas_size)
>  {
>      int ret;
>      int i;
> +    uint32_t lrdr_capacity[5];
> 
>      ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
>      if (ret < 0) {
> @@ -604,6 +606,28 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
>          }
> 
>      }
> +
> +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#address-cells", 0x2);
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add #address-cells rtas property\n");
> +    }
> +
> +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#size-cells", 0x2);
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add #size-cells rtas property\n");
> +    }
> +
> +    lrdr_capacity[0] = cpu_to_be32(spapr->maxram_limit >> 32);
> +    lrdr_capacity[1] = cpu_to_be32(spapr->maxram_limit & 0xffffffff);
> +    lrdr_capacity[2] = 0;
> +    lrdr_capacity[3] = cpu_to_be32(SPAPR_MIN_MEMORY_BLOCK_SIZE);
> +    lrdr_capacity[4] = cpu_to_be32(max_cpus/smp_threads);
> +    ret = qemu_fdt_setprop(fdt, "/rtas", "ibm,lrdr-capacity", lrdr_capacity,
> +                     sizeof(lrdr_capacity));
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add ibm,lrdr-capacity rtas property\n");
> +    }
> +

The property seems simple enough, but would be worthwhile to add a description
of how/when it's used in a new section of docs/specs/ppc-spapr-hotplug.txt to
keep the documentation complete

>      return 0;
>  }
> 
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 831db6b..ae8b4e1 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -18,6 +18,7 @@ typedef struct sPAPREnvironment {
>      XICSState *icp;
> 
>      hwaddr ram_limit;
> +    hwaddr maxram_limit;
>      void *htab;
>      uint32_t htab_shift;
>      hwaddr rma_size;
> @@ -444,8 +445,8 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn);
>  target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
>                               uint32_t token, uint32_t nargs, target_ulong args,
>                               uint32_t nret, target_ulong rets);
> -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> -                                 hwaddr rtas_size);
> +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> +                                 hwaddr rtas_addr, hwaddr rtas_size);
> 
>  #define SPAPR_TCE_PAGE_SHIFT   12
>  #define SPAPR_TCE_PAGE_SIZE    (1ULL << SPAPR_TCE_PAGE_SHIFT)
> @@ -479,6 +480,7 @@ struct sPAPRTCETable {
>  };
> 
>  #define TIMEBASE_FREQ           512000000ULL
> +#define SPAPR_MIN_MEMORY_BLOCK_SIZE (1 << 28) /* 256MB */

Is this actually the min, or a set increment size? Documentation suggests
the latter, in which case the naming is a little confusing.

> 
>  void spapr_events_init(sPAPREnvironment *spapr);
>  void spapr_events_fdt_skel(void *fdt, uint32_t epow_irq);
> -- 
> 2.1.0
David Gibson Jan. 29, 2015, 1:16 a.m. UTC | #2 
On Thu, Jan 08, 2015 at 11:40:12AM +0530, Bharata B Rao wrote:
> Add support for ibm,lrdr-capacity since this is needed by the guest
> kernel to know about the possible hot-pluggable CPUs and Memory.
> 
> Define minimum hotpluggable memory size as 256MB and start storing maximum
> possible memory for the guest in sPAPREnvironment.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> ---
>  hw/ppc/spapr.c         |  3 ++-
>  hw/ppc/spapr_rtas.c    | 28 ++++++++++++++++++++++++++--
>  include/hw/ppc/spapr.h |  6 ++++--
>  3 files changed, 32 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index f49b0fa..515d770 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -775,7 +775,7 @@ static void spapr_finalize_fdt(sPAPREnvironment *spapr,
>      }
>  
>      /* RTAS */
> -    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size);
> +    ret = spapr_rtas_device_tree_setup(spapr, fdt, rtas_addr, rtas_size);
>      if (ret < 0) {
>          fprintf(stderr, "Couldn't set up RTAS device tree properties\n");
>      }
> @@ -1473,6 +1473,7 @@ static void ppc_spapr_init(MachineState *machine)
>  
>      /* allocate RAM */
>      spapr->ram_limit = ram_size;
> +    spapr->maxram_limit = machine->maxram_size;

There's now a bunch of duplication between sPAPREnvironment and
MachineState - it looks like we should really fold sPAPREnvironment
into a subclass of MachineState, but that's probably a project for
another day.

>      memory_region_allocate_system_memory(ram, NULL, "ppc_spapr.ram",
>                                           spapr->ram_limit);
>      memory_region_add_subregion(sysmem, 0, ram);
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index d847f45..e8a0f21 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -29,6 +29,7 @@
>  #include "sysemu/char.h"
>  #include "hw/qdev.h"
>  #include "sysemu/device_tree.h"
> +#include "sysemu/cpus.h"
>  
>  #include "hw/ppc/spapr.h"
>  #include "hw/ppc/spapr_vio.h"
> @@ -551,11 +552,12 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn)
>      rtas_table[token].fn = fn;
>  }
>  
> -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> -                                 hwaddr rtas_size)
> +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> +                                 hwaddr rtas_addr, hwaddr rtas_size)
>  {
>      int ret;
>      int i;
> +    uint32_t lrdr_capacity[5];
>  
>      ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
>      if (ret < 0) {
> @@ -604,6 +606,28 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
>          }
>  
>      }
> +
> +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#address-cells", 0x2);
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add #address-cells rtas property\n");
> +    }
> +
> +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#size-cells", 0x2);
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add #size-cells rtas property\n");
> +    }

It's not clear what adding #address-cells and #size-cells has to do
with this, and these properties generally don't make sense on a node
without children.

> +    lrdr_capacity[0] = cpu_to_be32(spapr->maxram_limit >> 32);
> +    lrdr_capacity[1] = cpu_to_be32(spapr->maxram_limit & 0xffffffff);
> +    lrdr_capacity[2] = 0;
> +    lrdr_capacity[3] = cpu_to_be32(SPAPR_MIN_MEMORY_BLOCK_SIZE);
> +    lrdr_capacity[4] = cpu_to_be32(max_cpus/smp_threads);
> +    ret = qemu_fdt_setprop(fdt, "/rtas", "ibm,lrdr-capacity", lrdr_capacity,
> +                     sizeof(lrdr_capacity));
> +    if (ret < 0) {
> +        fprintf(stderr, "Couldn't add ibm,lrdr-capacity rtas property\n");
> +    }
> +
>      return 0;
>  }
>  
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 831db6b..ae8b4e1 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -18,6 +18,7 @@ typedef struct sPAPREnvironment {
>      XICSState *icp;
>  
>      hwaddr ram_limit;
> +    hwaddr maxram_limit;
>      void *htab;
>      uint32_t htab_shift;
>      hwaddr rma_size;
> @@ -444,8 +445,8 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn);
>  target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
>                               uint32_t token, uint32_t nargs, target_ulong args,
>                               uint32_t nret, target_ulong rets);
> -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> -                                 hwaddr rtas_size);
> +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> +                                 hwaddr rtas_addr, hwaddr rtas_size);
>  
>  #define SPAPR_TCE_PAGE_SHIFT   12
>  #define SPAPR_TCE_PAGE_SIZE    (1ULL << SPAPR_TCE_PAGE_SHIFT)
> @@ -479,6 +480,7 @@ struct sPAPRTCETable {
>  };
>  
>  #define TIMEBASE_FREQ           512000000ULL
> +#define SPAPR_MIN_MEMORY_BLOCK_SIZE (1 << 28) /* 256MB */
>  
>  void spapr_events_init(sPAPREnvironment *spapr);
>  void spapr_events_fdt_skel(void *fdt, uint32_t epow_irq);
Bharata B Rao Jan. 30, 2015, 7:50 a.m. UTC | #3 
On Thu, Jan 29, 2015 at 12:16:09PM +1100, David Gibson wrote:
> On Thu, Jan 08, 2015 at 11:40:12AM +0530, Bharata B Rao wrote:
> > -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> > -                                 hwaddr rtas_size)
> > +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> > +                                 hwaddr rtas_addr, hwaddr rtas_size)
> >  {
> >      int ret;
> >      int i;
> > +    uint32_t lrdr_capacity[5];
> >  
> >      ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
> >      if (ret < 0) {
> > @@ -604,6 +606,28 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> >          }
> >  
> >      }
> > +
> > +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#address-cells", 0x2);
> > +    if (ret < 0) {
> > +        fprintf(stderr, "Couldn't add #address-cells rtas property\n");
> > +    }
> > +
> > +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#size-cells", 0x2);
> > +    if (ret < 0) {
> > +        fprintf(stderr, "Couldn't add #size-cells rtas property\n");
> > +    }
> 
> It's not clear what adding #address-cells and #size-cells has to do
> with this, and these properties generally don't make sense on a node
> without children.

Yes, those aren't needed, will remove them.

Regards,
Bharata.
Bharata B Rao Jan. 30, 2015, 8:51 a.m. UTC | #4 
On Thu, Jan 22, 2015 at 03:55:40PM -0600, Michael Roth wrote:
> Quoting Bharata B Rao (2015-01-08 00:10:12)
> > Add support for ibm,lrdr-capacity since this is needed by the guest
> > kernel to know about the possible hot-pluggable CPUs and Memory.
> > 
> > Define minimum hotpluggable memory size as 256MB and start storing maximum
> > possible memory for the guest in sPAPREnvironment.
> > 
> > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> > ---
> >  hw/ppc/spapr.c         |  3 ++-
> >  hw/ppc/spapr_rtas.c    | 28 ++++++++++++++++++++++++++--
> >  include/hw/ppc/spapr.h |  6 ++++--
> >  3 files changed, 32 insertions(+), 5 deletions(-)
> > 
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index f49b0fa..515d770 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -775,7 +775,7 @@ static void spapr_finalize_fdt(sPAPREnvironment *spapr,
> >      }
> > 
> >      /* RTAS */
> > -    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size);
> > +    ret = spapr_rtas_device_tree_setup(spapr, fdt, rtas_addr, rtas_size);
> >      if (ret < 0) {
> >          fprintf(stderr, "Couldn't set up RTAS device tree properties\n");
> >      }
> > @@ -1473,6 +1473,7 @@ static void ppc_spapr_init(MachineState *machine)
> > 
> >      /* allocate RAM */
> >      spapr->ram_limit = ram_size;
> > +    spapr->maxram_limit = machine->maxram_size;
> >      memory_region_allocate_system_memory(ram, NULL, "ppc_spapr.ram",
> >                                           spapr->ram_limit);
> >      memory_region_add_subregion(sysmem, 0, ram);
> > diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> > index d847f45..e8a0f21 100644
> > --- a/hw/ppc/spapr_rtas.c
> > +++ b/hw/ppc/spapr_rtas.c
> > @@ -29,6 +29,7 @@
> >  #include "sysemu/char.h"
> >  #include "hw/qdev.h"
> >  #include "sysemu/device_tree.h"
> > +#include "sysemu/cpus.h"
> > 
> >  #include "hw/ppc/spapr.h"
> >  #include "hw/ppc/spapr_vio.h"
> > @@ -551,11 +552,12 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn)
> >      rtas_table[token].fn = fn;
> >  }
> > 
> > -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> > -                                 hwaddr rtas_size)
> > +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> > +                                 hwaddr rtas_addr, hwaddr rtas_size)
> >  {
> >      int ret;
> >      int i;
> > +    uint32_t lrdr_capacity[5];
> > 
> >      ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
> >      if (ret < 0) {
> > @@ -604,6 +606,28 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> >          }
> > 
> >      }
> > +
> > +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#address-cells", 0x2);
> > +    if (ret < 0) {
> > +        fprintf(stderr, "Couldn't add #address-cells rtas property\n");
> > +    }
> > +
> > +    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#size-cells", 0x2);
> > +    if (ret < 0) {
> > +        fprintf(stderr, "Couldn't add #size-cells rtas property\n");
> > +    }
> > +
> > +    lrdr_capacity[0] = cpu_to_be32(spapr->maxram_limit >> 32);
> > +    lrdr_capacity[1] = cpu_to_be32(spapr->maxram_limit & 0xffffffff);
> > +    lrdr_capacity[2] = 0;
> > +    lrdr_capacity[3] = cpu_to_be32(SPAPR_MIN_MEMORY_BLOCK_SIZE);
> > +    lrdr_capacity[4] = cpu_to_be32(max_cpus/smp_threads);
> > +    ret = qemu_fdt_setprop(fdt, "/rtas", "ibm,lrdr-capacity", lrdr_capacity,
> > +                     sizeof(lrdr_capacity));
> > +    if (ret < 0) {
> > +        fprintf(stderr, "Couldn't add ibm,lrdr-capacity rtas property\n");
> > +    }
> > +
> 
> The property seems simple enough, but would be worthwhile to add a description
> of how/when it's used in a new section of docs/specs/ppc-spapr-hotplug.txt to
> keep the documentation complete

Sure.

> 
> >      return 0;
> >  }
> > 
> > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> > index 831db6b..ae8b4e1 100644
> > --- a/include/hw/ppc/spapr.h
> > +++ b/include/hw/ppc/spapr.h
> > @@ -18,6 +18,7 @@ typedef struct sPAPREnvironment {
> >      XICSState *icp;
> > 
> >      hwaddr ram_limit;
> > +    hwaddr maxram_limit;
> >      void *htab;
> >      uint32_t htab_shift;
> >      hwaddr rma_size;
> > @@ -444,8 +445,8 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn);
> >  target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
> >                               uint32_t token, uint32_t nargs, target_ulong args,
> >                               uint32_t nret, target_ulong rets);
> > -int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
> > -                                 hwaddr rtas_size);
> > +int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
> > +                                 hwaddr rtas_addr, hwaddr rtas_size);
> > 
> >  #define SPAPR_TCE_PAGE_SHIFT   12
> >  #define SPAPR_TCE_PAGE_SIZE    (1ULL << SPAPR_TCE_PAGE_SHIFT)
> > @@ -479,6 +480,7 @@ struct sPAPRTCETable {
> >  };
> > 
> >  #define TIMEBASE_FREQ           512000000ULL
> > +#define SPAPR_MIN_MEMORY_BLOCK_SIZE (1 << 28) /* 256MB */
> 
> Is this actually the min, or a set increment size? Documentation suggests
> the latter, in which case the naming is a little confusing.

I should just call it SPAPR_MEMORY_BLOCK_SIZE.

Thanks for your review.

Regards,
Bharata.
diff mbox

Patch

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index f49b0fa..515d770 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -775,7 +775,7 @@  static void spapr_finalize_fdt(sPAPREnvironment *spapr,
     }
 
     /* RTAS */
-    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size);
+    ret = spapr_rtas_device_tree_setup(spapr, fdt, rtas_addr, rtas_size);
     if (ret < 0) {
         fprintf(stderr, "Couldn't set up RTAS device tree properties\n");
     }
@@ -1473,6 +1473,7 @@  static void ppc_spapr_init(MachineState *machine)
 
     /* allocate RAM */
     spapr->ram_limit = ram_size;
+    spapr->maxram_limit = machine->maxram_size;
     memory_region_allocate_system_memory(ram, NULL, "ppc_spapr.ram",
                                          spapr->ram_limit);
     memory_region_add_subregion(sysmem, 0, ram);
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index d847f45..e8a0f21 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -29,6 +29,7 @@ 
 #include "sysemu/char.h"
 #include "hw/qdev.h"
 #include "sysemu/device_tree.h"
+#include "sysemu/cpus.h"
 
 #include "hw/ppc/spapr.h"
 #include "hw/ppc/spapr_vio.h"
@@ -551,11 +552,12 @@  void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn)
     rtas_table[token].fn = fn;
 }
 
-int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
-                                 hwaddr rtas_size)
+int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
+                                 hwaddr rtas_addr, hwaddr rtas_size)
 {
     int ret;
     int i;
+    uint32_t lrdr_capacity[5];
 
     ret = fdt_add_mem_rsv(fdt, rtas_addr, rtas_size);
     if (ret < 0) {
@@ -604,6 +606,28 @@  int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
         }
 
     }
+
+    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#address-cells", 0x2);
+    if (ret < 0) {
+        fprintf(stderr, "Couldn't add #address-cells rtas property\n");
+    }
+
+    ret = qemu_fdt_setprop_cell(fdt, "/rtas", "#size-cells", 0x2);
+    if (ret < 0) {
+        fprintf(stderr, "Couldn't add #size-cells rtas property\n");
+    }
+
+    lrdr_capacity[0] = cpu_to_be32(spapr->maxram_limit >> 32);
+    lrdr_capacity[1] = cpu_to_be32(spapr->maxram_limit & 0xffffffff);
+    lrdr_capacity[2] = 0;
+    lrdr_capacity[3] = cpu_to_be32(SPAPR_MIN_MEMORY_BLOCK_SIZE);
+    lrdr_capacity[4] = cpu_to_be32(max_cpus/smp_threads);
+    ret = qemu_fdt_setprop(fdt, "/rtas", "ibm,lrdr-capacity", lrdr_capacity,
+                     sizeof(lrdr_capacity));
+    if (ret < 0) {
+        fprintf(stderr, "Couldn't add ibm,lrdr-capacity rtas property\n");
+    }
+
     return 0;
 }
 
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 831db6b..ae8b4e1 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -18,6 +18,7 @@  typedef struct sPAPREnvironment {
     XICSState *icp;
 
     hwaddr ram_limit;
+    hwaddr maxram_limit;
     void *htab;
     uint32_t htab_shift;
     hwaddr rma_size;
@@ -444,8 +445,8 @@  void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn);
 target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
                              uint32_t token, uint32_t nargs, target_ulong args,
                              uint32_t nret, target_ulong rets);
-int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
-                                 hwaddr rtas_size);
+int spapr_rtas_device_tree_setup(sPAPREnvironment *spapr, void *fdt,
+                                 hwaddr rtas_addr, hwaddr rtas_size);
 
 #define SPAPR_TCE_PAGE_SHIFT   12
 #define SPAPR_TCE_PAGE_SIZE    (1ULL << SPAPR_TCE_PAGE_SHIFT)
@@ -479,6 +480,7 @@  struct sPAPRTCETable {
 };
 
 #define TIMEBASE_FREQ           512000000ULL
+#define SPAPR_MIN_MEMORY_BLOCK_SIZE (1 << 28) /* 256MB */
 
 void spapr_events_init(sPAPREnvironment *spapr);
 void spapr_events_fdt_skel(void *fdt, uint32_t epow_irq);