[PATCH-for-11.0 00/13] hw/sh4/r2d: Raise amount of RAM from 64 to 192 MB

[PATCH-for-11.0 00/13] hw/sh4/r2d: Raise amount of RAM from 64 to 192 MB

[Philippe Mathieu-Daudé]

It is possible to add more RAM on the R2D board:
- 1 real 64MB SDRAM
- 1 virtual 64MB SRAM (virtual because back then such
  SRAM size wouldn't exist).

Memory tree change with this series applied:

    $ diff -uw a b
    --- a  2025-11-24 10:48:58
    +++ b  2025-11-24 10:49:30
    @@ -1,4 +1,4 @@
    -QEMU 10.0.0 monitor - type 'help' for more information
    +QEMU 10.1.91 monitor - type 'help' for more information
     (qemu) info mtree -f
     FlatView #0
      AS "memory", root: system
    @@ -6,7 +6,7 @@
      Root memory region: system
       0000000000000000-0000000000ffffff (prio 0, romd): r2d.flash
       0000000004000000-000000000400003f (prio 0, i/o): r2d-fpga
    -  000000000c000000-000000000fffffff (prio 0, ram): r2d.sdram
    +  0000000008000000-000000000fffffff (prio 0, ram): ram
       0000000010000000-00000000107fffff (prio 0, ram): sm501.local
       0000000013e00000-0000000013e0006b (prio 0, i/o): sm501-system-config
       0000000013e10040-0000000013e10053 (prio 0, i/o): sm501-i2c
    @@ -16,6 +16,7 @@
       0000000013f00000-0000000013f00053 (prio 0, i/o): sm501-2d-engine
       000000001400080c-000000001400080f (prio 0, i/o): ide-mmio.2
       0000000014001000-000000001400101f (prio 0, i/o): ide-mmio.1
    +  0000000018000000-000000001bffffff (prio 0, ram): ram @0000000008000000
       000000001e080000-000000001e080003 (prio 0, i/o): intc @000000001e080000
       000000001e080040-000000001e080043 (prio 0, i/o): intc @000000001e080040
       000000001e080060-000000001e080063 (prio 0, i/o): intc @000000001e080060

Philippe Mathieu-Daudé (13):
  hw/sh4/r2d: Bail out early if user request invalid RAM size
  hw/sh4/r2d: Define BOOT_PARAMS_BASE
  hw/sh4/r2d: Introduce sdram_base and sdram_size variables
  hw/sh4/r2d: Use memdev allocation for RAM
  hw/sh4/r2d: Reword SH7750_BCR1 and SH7750_BCR2 initialization comments
  hw/sh4/r2d: Configure flash (CS#0) as 16-bit accessible
  hw/sh4/r2d: Introduce EXT_CS_BASE() macro and use it for SDRAM
  hw/sh4/r2d: Use EXT_CS_BASE() macro for boot flash device
  hw/sh4/r2d: Use EXT_CS_BASE() macro for FPGA device
  hw/sh4/r2d: Use EXT_CS_BASE() macro for display controller
  hw/sh4/r2d: Use EXT_CS_BASE() macro for pseudo ISA bus
  hw/sh4/r2d: Add 64MB of SDRAM in CS#2
  hw/sh4/r2d: Add 64MB of SRAM in CS#6

 hw/sh4/r2d.c | 76 ++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 56 insertions(+), 20 deletions(-)

-- 
2.51.0

[PATCH-for-11.0 01/13] hw/sh4/r2d: Bail out early if user request invalid RAM size

[Philippe Mathieu-Daudé]

Do not give false expectations, as this machine only
uses 64MB of RAM.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 010be6d5394..56da48f64cb 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -251,6 +251,14 @@ static void r2d_init(MachineState *machine)
     USBBus *usb_bus;
     r2d_fpga_t *fpga;
 
+    switch (machine->ram_size) {
+    case 64 * MiB:
+        break;
+    default:
+        error_report("This machine can only use 64M of memory");
+        exit(EXIT_FAILURE);
+    }
+
     cpu = SUPERH_CPU(cpu_create(machine->cpu_type));
     env = &cpu->env;
 
-- 
2.51.0

[PATCH-for-11.0 02/13] hw/sh4/r2d: Define BOOT_PARAMS_BASE

[Philippe Mathieu-Daudé]

Linux expects the boot_params structure at a fixed location.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 56da48f64cb..5f8c034e1af 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -53,6 +53,7 @@
 
 #define SM501_VRAM_SIZE 0x800000
 
+#define BOOT_PARAMS_BASE 0x0c000000
 #define BOOT_PARAMS_OFFSET 0x0010000
 /* CONFIG_BOOT_LINK_OFFSET of Linux kernel */
 #define LINUX_LOAD_OFFSET  0x0800000
@@ -383,7 +384,7 @@ static void r2d_init(MachineState *machine)
     }
 
     rom_add_blob_fixed("boot_params", &boot_params, sizeof(boot_params),
-                       SDRAM_BASE + BOOT_PARAMS_OFFSET);
+                       BOOT_PARAMS_BASE + BOOT_PARAMS_OFFSET);
 }
 
 static void r2d_machine_init(MachineClass *mc)
-- 
2.51.0

[PATCH-for-11.0 03/13] hw/sh4/r2d: Introduce sdram_base and sdram_size variables

[Philippe Mathieu-Daudé]

Soon RAM base / size won't be fixed, so introduce local
variables for them.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 5f8c034e1af..51c7c3e2e07 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -251,9 +251,12 @@ static void r2d_init(MachineState *machine)
     PCIBus *pci_bus;
     USBBus *usb_bus;
     r2d_fpga_t *fpga;
+    hwaddr sdram_base;
+    uint64_t sdram_size = SDRAM_SIZE;
 
     switch (machine->ram_size) {
     case 64 * MiB:
+        sdram_base = SDRAM_BASE;
         break;
     default:
         error_report("This machine can only use 64M of memory");
@@ -269,8 +272,8 @@ static void r2d_init(MachineState *machine)
     qemu_register_reset(main_cpu_reset, reset_info);
 
     /* Allocate memory space */
-    memory_region_init_ram(sdram, NULL, "r2d.sdram", SDRAM_SIZE, &error_fatal);
-    memory_region_add_subregion(address_space_mem, SDRAM_BASE, sdram);
+    memory_region_init_ram(sdram, NULL, "r2d.sdram", sdram_size, &error_fatal);
+    memory_region_add_subregion(address_space_mem, sdram_base, sdram);
     /* Register peripherals */
     s = sh7750_init(cpu, address_space_mem);
     fpga = r2d_fpga_init(address_space_mem, 0x04000000, sh7750_irl(s));
@@ -338,7 +341,7 @@ static void r2d_init(MachineState *machine)
         int kernel_size;
 
         kernel_size = load_image_targphys(kernel_filename,
-                                        SDRAM_BASE + LINUX_LOAD_OFFSET,
+                                        sdram_base + LINUX_LOAD_OFFSET,
                                         INITRD_LOAD_OFFSET - LINUX_LOAD_OFFSET,
                                         NULL);
         if (kernel_size < 0) {
@@ -352,15 +355,15 @@ static void r2d_init(MachineState *machine)
         address_space_stw(&address_space_memory, SH7750_BCR2, 3 << (3 * 2),
                           MEMTXATTRS_UNSPECIFIED, NULL); /* cs3 32bit */
         /* Start from P2 area */
-        reset_info->vector = (SDRAM_BASE + LINUX_LOAD_OFFSET) | 0xa0000000;
+        reset_info->vector = (sdram_base + LINUX_LOAD_OFFSET) | 0xa0000000;
     }
 
     if (initrd_filename) {
         int initrd_size;
 
         initrd_size = load_image_targphys(initrd_filename,
-                                          SDRAM_BASE + INITRD_LOAD_OFFSET,
-                                          SDRAM_SIZE - INITRD_LOAD_OFFSET,
+                                          sdram_base + INITRD_LOAD_OFFSET,
+                                          sdram_size - INITRD_LOAD_OFFSET,
                                           NULL);
 
         if (initrd_size < 0) {
-- 
2.51.0

[PATCH-for-11.0 04/13] hw/sh4/r2d: Use memdev allocation for RAM

[Philippe Mathieu-Daudé]

Memdev allocated MemoryRegion is initialized by generic code,
so board only needs to opt in to memdev scheme by providing
MachineClass::default_ram_id and using MachineState::ram
instead of manually initializing RAM memory region.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 51c7c3e2e07..5fd06b3b731 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -252,7 +252,7 @@ static void r2d_init(MachineState *machine)
     USBBus *usb_bus;
     r2d_fpga_t *fpga;
     hwaddr sdram_base;
-    uint64_t sdram_size = SDRAM_SIZE;
+    uint64_t sdram_size = machine->ram_size;
 
     switch (machine->ram_size) {
     case 64 * MiB:
@@ -272,7 +272,7 @@ static void r2d_init(MachineState *machine)
     qemu_register_reset(main_cpu_reset, reset_info);
 
     /* Allocate memory space */
-    memory_region_init_ram(sdram, NULL, "r2d.sdram", sdram_size, &error_fatal);
+    memory_region_init_alias(sdram, NULL, "sdram", machine->ram, 0, sdram_size);
     memory_region_add_subregion(address_space_mem, sdram_base, sdram);
     /* Register peripherals */
     s = sh7750_init(cpu, address_space_mem);
@@ -396,6 +396,8 @@ static void r2d_machine_init(MachineClass *mc)
     mc->init = r2d_init;
     mc->block_default_type = IF_IDE;
     mc->default_cpu_type = TYPE_SH7751R_CPU;
+    mc->default_ram_size = 64 * MiB;
+    mc->default_ram_id = "ram";
     mc->default_nic = "rtl8139";
 }
 
-- 
2.51.0

[PATCH-for-11.0 05/13] hw/sh4/r2d: Reword SH7750_BCR1 and SH7750_BCR2 initialization comments

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 5fd06b3b731..9de4944ecee 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -350,10 +350,12 @@ static void r2d_init(MachineState *machine)
         }
 
         /* initialization which should be done by firmware */
-        address_space_stl(&address_space_memory, SH7750_BCR1, 1 << 3,
-                          MEMTXATTRS_UNSPECIFIED, NULL); /* cs3 SDRAM */
-        address_space_stw(&address_space_memory, SH7750_BCR2, 3 << (3 * 2),
-                          MEMTXATTRS_UNSPECIFIED, NULL); /* cs3 32bit */
+        address_space_stl(&address_space_memory, SH7750_BCR1,
+                          (1 << 3) | /* Areas 3  accessed as SDRAM */
+                          0, MEMTXATTRS_UNSPECIFIED, NULL);
+        address_space_stw(&address_space_memory, SH7750_BCR2,
+                          (0b11 << 2 * 3) | /* Area 3 Bus width is 32 bits */
+                          0, MEMTXATTRS_UNSPECIFIED, NULL);
         /* Start from P2 area */
         reset_info->vector = (sdram_base + LINUX_LOAD_OFFSET) | 0xa0000000;
     }
-- 
2.51.0

[PATCH-for-11.0 06/13] hw/sh4/r2d: Configure flash (CS#0) as 16-bit accessible

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 9de4944ecee..12232fabbdf 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -355,6 +355,7 @@ static void r2d_init(MachineState *machine)
                           0, MEMTXATTRS_UNSPECIFIED, NULL);
         address_space_stw(&address_space_memory, SH7750_BCR2,
                           (0b11 << 2 * 3) | /* Area 3 Bus width is 32 bits */
+                          (0b10 << 14) |    /* Area 0 Bus Width is 16 bits */
                           0, MEMTXATTRS_UNSPECIFIED, NULL);
         /* Start from P2 area */
         reset_info->vector = (sdram_base + LINUX_LOAD_OFFSET) | 0xa0000000;
-- 
2.51.0

[PATCH-for-11.0 07/13] hw/sh4/r2d: Introduce EXT_CS_BASE() macro and use it for SDRAM

[Philippe Mathieu-Daudé]

The SH7751 memory controller can access 7 external banks.
The 64MB of SDRAM is on bank #3. Introduce the EXT_CS_BASE()
macro and use it for SDRAM.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 12232fabbdf..ecbc1ec2a98 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -45,10 +45,11 @@
 #include "hw/block/flash.h"
 #include "exec/tswap.h"
 
-#define FLASH_BASE 0x00000000
+#define EXT_CS_SIZE (64 * MiB)
+#define EXT_CS_BASE(cs_index) ((cs_index) * EXT_CS_SIZE)
+
 #define FLASH_SIZE (16 * MiB)
 
-#define SDRAM_BASE 0x0c000000 /* Physical location of SDRAM: Area 3 */
 #define SDRAM_SIZE 0x04000000
 
 #define SM501_VRAM_SIZE 0x800000
@@ -256,7 +257,7 @@ static void r2d_init(MachineState *machine)
 
     switch (machine->ram_size) {
     case 64 * MiB:
-        sdram_base = SDRAM_BASE;
+        sdram_base = EXT_CS_BASE(3); /* 64M @CS3 */
         break;
     default:
         error_report("This machine can only use 64M of memory");
-- 
2.51.0

[PATCH-for-11.0 08/13] hw/sh4/r2d: Use EXT_CS_BASE() macro for boot flash device

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index ecbc1ec2a98..26edcabf2c0 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -252,6 +252,7 @@ static void r2d_init(MachineState *machine)
     PCIBus *pci_bus;
     USBBus *usb_bus;
     r2d_fpga_t *fpga;
+    const hwaddr flash_base = EXT_CS_BASE(0);
     hwaddr sdram_base;
     uint64_t sdram_size = machine->ram_size;
 
@@ -321,7 +322,7 @@ static void r2d_init(MachineState *machine)
      * addressable in words of 16bit.
      */
     dinfo = drive_get(IF_PFLASH, 0, 0);
-    pflash_cfi02_register(0x0, "r2d.flash", FLASH_SIZE,
+    pflash_cfi02_register(flash_base, "r2d.flash", FLASH_SIZE,
                           dinfo ? blk_by_legacy_dinfo(dinfo) : NULL,
                           64 * KiB, 1, 2, 0x0001, 0x227e, 0x2220, 0x2200,
                           0x555, 0x2aa, 0);
-- 
2.51.0

[PATCH-for-11.0 09/13] hw/sh4/r2d: Use EXT_CS_BASE() macro for FPGA device

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 26edcabf2c0..2229cc6fe66 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -253,6 +253,7 @@ static void r2d_init(MachineState *machine)
     USBBus *usb_bus;
     r2d_fpga_t *fpga;
     const hwaddr flash_base = EXT_CS_BASE(0);
+    const hwaddr fpga_base = EXT_CS_BASE(1);
     hwaddr sdram_base;
     uint64_t sdram_size = machine->ram_size;
 
@@ -278,7 +279,7 @@ static void r2d_init(MachineState *machine)
     memory_region_add_subregion(address_space_mem, sdram_base, sdram);
     /* Register peripherals */
     s = sh7750_init(cpu, address_space_mem);
-    fpga = r2d_fpga_init(address_space_mem, 0x04000000, sh7750_irl(s));
+    fpga = r2d_fpga_init(address_space_mem, fpga_base, sh7750_irl(s));
 
     dev = qdev_new("sh_pci");
     busdev = SYS_BUS_DEVICE(dev);
-- 
2.51.0

[PATCH-for-11.0 10/13] hw/sh4/r2d: Use EXT_CS_BASE() macro for display controller

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 2229cc6fe66..75878abe946 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -254,6 +254,7 @@ static void r2d_init(MachineState *machine)
     r2d_fpga_t *fpga;
     const hwaddr flash_base = EXT_CS_BASE(0);
     const hwaddr fpga_base = EXT_CS_BASE(1);
+    const hwaddr sm501_base = EXT_CS_BASE(4);
     hwaddr sdram_base;
     uint64_t sdram_size = machine->ram_size;
 
@@ -295,11 +296,11 @@ static void r2d_init(MachineState *machine)
     dev = qdev_new("sysbus-sm501");
     busdev = SYS_BUS_DEVICE(dev);
     qdev_prop_set_uint32(dev, "vram-size", SM501_VRAM_SIZE);
-    qdev_prop_set_uint64(dev, "dma-offset", 0x10000000);
+    qdev_prop_set_uint64(dev, "dma-offset", sm501_base);
     qdev_prop_set_chr(dev, "chardev", serial_hd(2));
     sysbus_realize_and_unref(busdev, &error_fatal);
-    sysbus_mmio_map(busdev, 0, 0x10000000);
-    sysbus_mmio_map(busdev, 1, 0x13e00000);
+    sysbus_mmio_map(busdev, 0, sm501_base);
+    sysbus_mmio_map(busdev, 1, sm501_base + 0x3e00000);
     sysbus_connect_irq(busdev, 0, &fpga->irq[SM501]);
 
     /* onboard CF (True IDE mode, Master only). */
-- 
2.51.0

[PATCH-for-11.0 11/13] hw/sh4/r2d: Use EXT_CS_BASE() macro for pseudo ISA bus

[Philippe Mathieu-Daudé]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 75878abe946..df62f7a48a9 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -255,6 +255,7 @@ static void r2d_init(MachineState *machine)
     const hwaddr flash_base = EXT_CS_BASE(0);
     const hwaddr fpga_base = EXT_CS_BASE(1);
     const hwaddr sm501_base = EXT_CS_BASE(4);
+    const hwaddr isa_base = EXT_CS_BASE(5);
     hwaddr sdram_base;
     uint64_t sdram_size = machine->ram_size;
 
@@ -310,8 +311,8 @@ static void r2d_init(MachineState *machine)
     sysbus_connect_irq(busdev, 0, &fpga->irq[CF_IDE]);
     qdev_prop_set_uint32(dev, "shift", 1);
     sysbus_realize_and_unref(busdev, &error_fatal);
-    sysbus_mmio_map(busdev, 0, 0x14001000);
-    sysbus_mmio_map(busdev, 1, 0x1400080c);
+    sysbus_mmio_map(busdev, 0, isa_base + 0x1000);
+    sysbus_mmio_map(busdev, 1, isa_base + 0x080c);
     mmio_ide_init_drives(dev, dinfo, NULL);
 
     /*
-- 
2.51.0

[PATCH-for-11.0 12/13] hw/sh4/r2d: Add 64MB of SDRAM in CS#2

[Philippe Mathieu-Daudé]

Expand maximum memory from 64MB to 128MB.

Inspired-by: Rob Landley <rob@landley.net>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index df62f7a48a9..f5bc7c46965 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -263,8 +263,11 @@ static void r2d_init(MachineState *machine)
     case 64 * MiB:
         sdram_base = EXT_CS_BASE(3); /* 64M @CS3 */
         break;
+    case 128 * MiB:
+        sdram_base = EXT_CS_BASE(2); /* 64M @CS2, 64M@CS3 */
+        break;
     default:
-        error_report("This machine can only use 64M of memory");
+        error_report("This machine can only use 64M or 128M of memory");
         exit(EXIT_FAILURE);
     }
 
@@ -356,9 +359,11 @@ static void r2d_init(MachineState *machine)
 
         /* initialization which should be done by firmware */
         address_space_stl(&address_space_memory, SH7750_BCR1,
+                          (1 << 2) | /* Areas 2  accessed as SDRAM */
                           (1 << 3) | /* Areas 3  accessed as SDRAM */
                           0, MEMTXATTRS_UNSPECIFIED, NULL);
         address_space_stw(&address_space_memory, SH7750_BCR2,
+                          (0b11 << 2 * 2) | /* Area 2 Bus width is 32 bits */
                           (0b11 << 2 * 3) | /* Area 3 Bus width is 32 bits */
                           (0b10 << 14) |    /* Area 0 Bus Width is 16 bits */
                           0, MEMTXATTRS_UNSPECIFIED, NULL);
-- 
2.51.0

[PATCH-for-11.0 13/13] hw/sh4/r2d: Add 64MB of SRAM in CS#6

[Philippe Mathieu-Daudé]

Expand maximum memory from 128MB to 192MB.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sh4/r2d.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index f5bc7c46965..445cc9a246d 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -245,6 +245,7 @@ static void r2d_init(MachineState *machine)
     ResetData *reset_info;
     struct SH7750State *s;
     MemoryRegion *sdram = g_new(MemoryRegion, 1);
+    MemoryRegion *sram = g_new(MemoryRegion, 1);
     DriveInfo *dinfo;
     DeviceState *dev;
     SysBusDevice *busdev;
@@ -266,8 +267,15 @@ static void r2d_init(MachineState *machine)
     case 128 * MiB:
         sdram_base = EXT_CS_BASE(2); /* 64M @CS2, 64M@CS3 */
         break;
+    case 192 * MiB:
+        sdram_base = EXT_CS_BASE(2); /* 64M @CS2, 64M@CS3, 64M@CS6 */
+        sdram_size = 128 * MiB;
+        memory_region_init_alias(sram, NULL,
+                                 "sram", machine->ram, 128 * MiB, 64 * MiB);
+        memory_region_add_subregion(address_space_mem, EXT_CS_BASE(6), sram);
+        break;
     default:
-        error_report("This machine can only use 64M or 128M of memory");
+        error_report("This machine can only use 64M, 128M or 192M of memory");
         exit(EXIT_FAILURE);
     }
 
@@ -365,6 +373,7 @@ static void r2d_init(MachineState *machine)
         address_space_stw(&address_space_memory, SH7750_BCR2,
                           (0b11 << 2 * 2) | /* Area 2 Bus width is 32 bits */
                           (0b11 << 2 * 3) | /* Area 3 Bus width is 32 bits */
+                          (0b11 << 2 * 6) | /* Area 6 Bus width is 32 bits */
                           (0b10 << 14) |    /* Area 0 Bus Width is 16 bits */
                           0, MEMTXATTRS_UNSPECIFIED, NULL);
         /* Start from P2 area */
-- 
2.51.0