[Qemu-riscv] [RFC v1 2/5] hw/riscv: Add support for loading a firmware

[Alistair Francis]

Add support for loading a firmware file for the virt machine and the
SiFive U. This can be run with the following command:

    qemu-system-riscv64 -machine virt -bios fw_jump.elf -kernel vmlinux

Signed-off-by: Alistair Francis <address@hidden>
---
 hw/riscv/boot.c         | 41 +++++++++++++++++++++++++++++++++++++++--
 hw/riscv/sifive_e.c     |  2 +-
 hw/riscv/sifive_u.c     |  6 +++++-
 hw/riscv/spike.c        |  6 +++---
 hw/riscv/virt.c         |  7 ++++++-
 include/hw/riscv/boot.h |  4 +++-
 6 files changed, 57 insertions(+), 9 deletions(-)

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index 62f94aaf8a..392ca0cb2e 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -23,13 +23,50 @@
 #include "exec/cpu-defs.h"
 #include "hw/loader.h"
 #include "hw/riscv/boot.h"
+#include "hw/boards.h"
 #include "elf.h"
 
-target_ulong riscv_load_kernel(const char *kernel_filename)
+#if defined(TARGET_RISCV32)
+# define KERNEL_BOOT_ADDRESS 0x80400000
+#else
+# define KERNEL_BOOT_ADDRESS 0x80200000
+#endif
+
+static uint64_t kernel_translate(void *opaque, uint64_t addr)
+{
+    MachineState *machine = opaque;
+
+    /*
+     * If the user specified a firmware move the kernel to the offset
+     * start address.
+     */
+    if (machine->firmware) {
+        return (addr & 0x7fffffff) + KERNEL_BOOT_ADDRESS;
+    } else {
+        return addr;
+    }
+}
+
+target_ulong riscv_load_firmware(const char *firmware_filename)
+{
+    uint64_t firmware_entry, firmware_start, firmware_end;
+
+    if (load_elf(firmware_filename, NULL, NULL, NULL,
+                 &firmware_entry, &firmware_start, &firmware_end,
+                 0, EM_RISCV, 1, 0) < 0) {
+        error_report("could not load firmware '%s'", firmware_filename);
+        exit(1);
+    }
+
+    return firmware_entry;
+}
+
+target_ulong riscv_load_kernel(MachineState *machine,
+                               const char *kernel_filename)
 {
     uint64_t kernel_entry, kernel_high;
 
-    if (load_elf(kernel_filename, NULL, NULL, NULL,
+    if (load_elf(kernel_filename, NULL, kernel_translate, machine,
                  &kernel_entry, NULL, &kernel_high,
                  0, EM_RISCV, 1, 0) < 0) {
         error_report("could not load kernel '%s'", kernel_filename);
diff --git a/hw/riscv/sifive_e.c b/hw/riscv/sifive_e.c
index 9d58ae362b..3695c686be 100644
--- a/hw/riscv/sifive_e.c
+++ b/hw/riscv/sifive_e.c
@@ -118,7 +118,7 @@ static void riscv_sifive_e_init(MachineState *machine)
                           memmap[SIFIVE_E_MROM].base, &address_space_memory);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        riscv_load_kernel(machine, machine->kernel_filename);
     }
 }
 
diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 1b9281bd4a..03a6c64d04 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -266,8 +266,12 @@ static void riscv_sifive_u_init(MachineState *machine)
     /* create device tree */
     create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
+    if (machine->firmware) {
+        riscv_load_firmware(machine->firmware);
+    }
+
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        riscv_load_kernel(machine, machine->kernel_filename);
     }
 
     /* reset vector */
diff --git a/hw/riscv/spike.c b/hw/riscv/spike.c
index e68be00a5f..81cef0dcea 100644
--- a/hw/riscv/spike.c
+++ b/hw/riscv/spike.c
@@ -186,7 +186,7 @@ static void spike_board_init(MachineState *machine)
                                 mask_rom);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        riscv_load_kernel(machine, machine->kernel_filename);
     }
 
     /* reset vector */
@@ -274,7 +274,7 @@ static void spike_v1_10_0_board_init(MachineState *machine)
                                 mask_rom);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        riscv_load_kernel(machine, machine->kernel_filename);
     }
 
     /* reset vector */
@@ -359,7 +359,7 @@ static void spike_v1_09_1_board_init(MachineState *machine)
                                 mask_rom);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        riscv_load_kernel(machine, machine->kernel_filename);
     }
 
     /* reset vector */
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 5f8c11471b..d3670b5a7c 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -380,8 +380,13 @@ static void riscv_virt_board_init(MachineState *machine)
     memory_region_add_subregion(system_memory, memmap[VIRT_MROM].base,
                                 mask_rom);
 
+    if (machine->firmware) {
+        riscv_load_firmware(machine->firmware);
+    }
+
     if (machine->kernel_filename) {
-        uint64_t kernel_entry = riscv_load_kernel(machine->kernel_filename);
+        uint64_t kernel_entry = riscv_load_kernel(machine,
+                                                  machine->kernel_filename);
 
         if (machine->initrd_filename) {
             hwaddr start;
diff --git a/include/hw/riscv/boot.h b/include/hw/riscv/boot.h
index f84fd6c2df..6f586939c7 100644
--- a/include/hw/riscv/boot.h
+++ b/include/hw/riscv/boot.h
@@ -20,7 +20,9 @@
 #ifndef RISCV_BOOT_H
 #define RISCV_BOOT_H
 
-target_ulong riscv_load_kernel(const char *kernel_filename);
+target_ulong riscv_load_firmware(const char *firmware_filename);
+target_ulong riscv_load_kernel(MachineState *machine,
+                               const char *kernel_filename);
 hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
                          uint64_t kernel_entry, hwaddr *start);
 
-- 
2.22.0