hw/riscv: virt: Enable booting S-mode firmware from pflash

To boot S-mode firmware payload like EDK2 from persistent
flash storage, qemu needs to pass the flash address as the
next_addr in fw_dynamic_info to the opensbi.

When both -kernel and -pflash options are provided in command line,
the kernel (and initrd if -initrd) will be copied to fw_cfg table.
The S-mode FW will load the kernel/initrd from fw_cfg table.

If only pflash is given but not -kernel, then it is the job of
of the S-mode firmware to locate and load the kernel.

In either case, update the kernel_entry with the flash address
so that the opensbi can jump to the entry point of the S-mode
firmware.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221004092351.18209-4-sunilvl@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index f6e8eafa28..e82bf27338 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -338,3 +338,32 @@ void riscv_setup_direct_kernel(hwaddr kernel_addr, hwaddr fdt_addr)
         riscv_cpu->env.fdt_addr = fdt_addr;
     }
 }
+
+void riscv_setup_firmware_boot(MachineState *machine)
+{
+    if (machine->kernel_filename) {
+        FWCfgState *fw_cfg;
+        fw_cfg = fw_cfg_find();
+
+        assert(fw_cfg);
+        /*
+         * Expose the kernel, the command line, and the initrd in fw_cfg.
+         * We don't process them here at all, it's all left to the
+         * firmware.
+         */
+        load_image_to_fw_cfg(fw_cfg,
+                             FW_CFG_KERNEL_SIZE, FW_CFG_KERNEL_DATA,
+                             machine->kernel_filename,
+                             true);
+        load_image_to_fw_cfg(fw_cfg,
+                             FW_CFG_INITRD_SIZE, FW_CFG_INITRD_DATA,
+                             machine->initrd_filename, false);
+
+        if (machine->kernel_cmdline) {
+            fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE,
+                           strlen(machine->kernel_cmdline) + 1);
+            fw_cfg_add_string(fw_cfg, FW_CFG_CMDLINE_DATA,
+                              machine->kernel_cmdline);
+        }
+    }
+}