riscv: Unify Qemu's reset vector code path

Currently, all riscv machines except sifive_u have identical reset vector
code implementations with memory addresses being different for all machines.
They can be easily combined into a single function in common code.

Move it to common function and let all the machines use the common function.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Tested-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20200701183949.398134-2-atish.patra@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index adb421b..3df8023 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -26,8 +26,11 @@
 #include "hw/loader.h"
 #include "hw/riscv/boot.h"
 #include "elf.h"
+#include "sysemu/device_tree.h"
 #include "sysemu/qtest.h"
 
+#include <libfdt.h>
+
 #if defined(TARGET_RISCV32)
 # define KERNEL_BOOT_ADDRESS 0x80400000
 #else
@@ -155,3 +158,46 @@ hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
 
     return *start + size;
 }
+
+void riscv_setup_rom_reset_vec(hwaddr start_addr, hwaddr rom_base,
+                               hwaddr rom_size, void *fdt)
+{
+    int i;
+
+    /* reset vector */
+    uint32_t reset_vec[8] = {
+        0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(dtb) */
+        0x02028593,                  /*     addi   a1, t0, %pcrel_lo(1b) */
+        0xf1402573,                  /*     csrr   a0, mhartid  */
+#if defined(TARGET_RISCV32)
+        0x0182a283,                  /*     lw     t0, 24(t0) */
+#elif defined(TARGET_RISCV64)
+        0x0182b283,                  /*     ld     t0, 24(t0) */
+#endif
+        0x00028067,                  /*     jr     t0 */
+        0x00000000,
+        start_addr,                  /* start: .dword */
+        0x00000000,
+                                     /* dtb: */
+    };
+
+    /* copy in the reset vector in little_endian byte order */
+    for (i = 0; i < sizeof(reset_vec) >> 2; i++) {
+        reset_vec[i] = cpu_to_le32(reset_vec[i]);
+    }
+    rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
+                          rom_base, &address_space_memory);
+
+    /* copy in the device tree */
+    if (fdt_pack(fdt) || fdt_totalsize(fdt) >
+        rom_size - sizeof(reset_vec)) {
+        error_report("not enough space to store device-tree");
+        exit(1);
+    }
+    qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt));
+    rom_add_blob_fixed_as("mrom.fdt", fdt, fdt_totalsize(fdt),
+                           rom_base + sizeof(reset_vec),
+                           &address_space_memory);
+
+    return;
+}