The HiFive Unleashed uses is25wp256 SPI NOR flash. There is currently no
model of this in QEMU, so to allow boot firmware developers to use QEMU
to target the Unleashed let's add a chunk of memory to represent the QSPI0
memory mapped flash. This can be targeted using QEMU's -device loader
command line option.

In the future we can look at adding a model for the is25wp256 flash.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
---
 hw/riscv/sifive_u.c         | 8 ++++++++
 include/hw/riscv/sifive_u.h | 1 +
 2 files changed, 9 insertions(+)

diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 1d255ad13e..bc0e01242b 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -71,6 +71,7 @@ static const struct MemmapEntry {
     [SIFIVE_U_UART0] =    { 0x10010000,     0x1000 },
     [SIFIVE_U_UART1] =    { 0x10011000,     0x1000 },
     [SIFIVE_U_OTP] =      { 0x10070000,     0x1000 },
+    [SIFIVE_U_FLASH0] =   { 0x20000000, 0x10000000 },
     [SIFIVE_U_DRAM] =     { 0x80000000,        0x0 },
     [SIFIVE_U_GEM] =      { 0x10090000,     0x2000 },
     [SIFIVE_U_GEM_MGMT] = { 0x100a0000,     0x1000 },
@@ -313,6 +314,7 @@ static void riscv_sifive_u_init(MachineState *machine)
     SiFiveUState *s = g_new0(SiFiveUState, 1);
     MemoryRegion *system_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
+    MemoryRegion *flash0 = g_new(MemoryRegion, 1);
     int i;
 
     /* Initialize SoC */
@@ -328,6 +330,12 @@ static void riscv_sifive_u_init(MachineState *machine)
     memory_region_add_subregion(system_memory, memmap[SIFIVE_U_DRAM].base,
                                 main_mem);
 
+    /* register QSPI0 Flash */
+    memory_region_init_ram(flash0, NULL, "riscv.sifive.u.flash0",
+                           memmap[SIFIVE_U_FLASH0].size, &error_fatal);
+    memory_region_add_subregion(system_memory, memmap[SIFIVE_U_FLASH0].base,
+                                flash0);
+
     /* create device tree */
     create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
diff --git a/include/hw/riscv/sifive_u.h b/include/hw/riscv/sifive_u.h
index 50e3620c02..2a08e2a5db 100644
--- a/include/hw/riscv/sifive_u.h
+++ b/include/hw/riscv/sifive_u.h
@@ -64,6 +64,7 @@ enum {
     SIFIVE_U_UART0,
     SIFIVE_U_UART1,
     SIFIVE_U_OTP,
+    SIFIVE_U_FLASH0,
     SIFIVE_U_DRAM,
     SIFIVE_U_GEM,
     SIFIVE_U_GEM_MGMT
-- 
2.23.0

On Fri, Sep 27, 2019 at 8:51 AM Alistair Francis
<alistair.francis@wdc.com> wrote:
>
> The HiFive Unleashed uses is25wp256 SPI NOR flash. There is currently no
> model of this in QEMU, so to allow boot firmware developers to use QEMU
> to target the Unleashed let's add a chunk of memory to represent the QSPI0
> memory mapped flash. This can be targeted using QEMU's -device loader
> command line option.
>
> In the future we can look at adding a model for the is25wp256 flash.
>
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> ---
>  hw/riscv/sifive_u.c         | 8 ++++++++
>  include/hw/riscv/sifive_u.h | 1 +
>  2 files changed, 9 insertions(+)
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>