[PATCH v5 1/7] target/riscv: Add fw_dynamic_info32 for booting RV32 OpenSBI

[LIU Zhiwei <zhiwei_liu@linux.alibaba.com>]

From: TANG Tiancheng <tangtiancheng.ttc@alibaba-inc.com>

RV32 OpenSBI need a fw_dynamic_info parameter with 32-bit fields instead
of target_ulong.

In RV64 QEMU, target_ulong is 64. So it is not right for booting RV32 OpenSBI.
We create a fw_dynmaic_info32 struct for this purpose.

Signed-off-by: TANG Tiancheng <tangtiancheng.ttc@alibaba-inc.com>
Reviewed-by: Liu Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---
 hw/riscv/boot.c                 | 35 ++++++++++++++++++++++-----------
 hw/riscv/sifive_u.c             |  3 ++-
 include/hw/riscv/boot.h         |  4 +++-
 include/hw/riscv/boot_opensbi.h | 29 +++++++++++++++++++++++++++
 4 files changed, 57 insertions(+), 14 deletions(-)

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index 47281ca853..1a2c1ff9e0 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -342,27 +342,33 @@ void riscv_load_fdt(hwaddr fdt_addr, void *fdt)
                         rom_ptr_for_as(&address_space_memory, fdt_addr, fdtsize));
 }
 
-void riscv_rom_copy_firmware_info(MachineState *machine, hwaddr rom_base,
-                                  hwaddr rom_size, uint32_t reset_vec_size,
+void riscv_rom_copy_firmware_info(MachineState *machine,
+                                  RISCVHartArrayState *harts,
+                                  hwaddr rom_base, hwaddr rom_size,
+                                  uint32_t reset_vec_size,
                                   uint64_t kernel_entry)
 {
+    struct fw_dynamic_info32 dinfo32;
     struct fw_dynamic_info dinfo;
     size_t dinfo_len;
 
-    if (sizeof(dinfo.magic) == 4) {
-        dinfo.magic = cpu_to_le32(FW_DYNAMIC_INFO_MAGIC_VALUE);
-        dinfo.version = cpu_to_le32(FW_DYNAMIC_INFO_VERSION);
-        dinfo.next_mode = cpu_to_le32(FW_DYNAMIC_INFO_NEXT_MODE_S);
-        dinfo.next_addr = cpu_to_le32(kernel_entry);
+    if (riscv_is_32bit(harts)) {
+        dinfo32.magic = cpu_to_le32(FW_DYNAMIC_INFO_MAGIC_VALUE);
+        dinfo32.version = cpu_to_le32(FW_DYNAMIC_INFO_VERSION);
+        dinfo32.next_mode = cpu_to_le32(FW_DYNAMIC_INFO_NEXT_MODE_S);
+        dinfo32.next_addr = cpu_to_le32(kernel_entry);
+        dinfo32.options = 0;
+        dinfo32.boot_hart = 0;
+        dinfo_len = sizeof(dinfo32);
     } else {
         dinfo.magic = cpu_to_le64(FW_DYNAMIC_INFO_MAGIC_VALUE);
         dinfo.version = cpu_to_le64(FW_DYNAMIC_INFO_VERSION);
         dinfo.next_mode = cpu_to_le64(FW_DYNAMIC_INFO_NEXT_MODE_S);
         dinfo.next_addr = cpu_to_le64(kernel_entry);
+        dinfo.options = 0;
+        dinfo.boot_hart = 0;
+        dinfo_len = sizeof(dinfo);
     }
-    dinfo.options = 0;
-    dinfo.boot_hart = 0;
-    dinfo_len = sizeof(dinfo);
 
     /**
      * copy the dynamic firmware info. This information is specific to
@@ -374,7 +380,10 @@ void riscv_rom_copy_firmware_info(MachineState *machine, hwaddr rom_base,
         exit(1);
     }
 
-    rom_add_blob_fixed_as("mrom.finfo", &dinfo, dinfo_len,
+    rom_add_blob_fixed_as("mrom.finfo",
+                           riscv_is_32bit(harts) ?
+                           (void *)&dinfo32 : (void *)&dinfo,
+                           dinfo_len,
                            rom_base + reset_vec_size,
                            &address_space_memory);
 }
@@ -430,7 +439,9 @@ void riscv_setup_rom_reset_vec(MachineState *machine, RISCVHartArrayState *harts
     }
     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
                           rom_base, &address_space_memory);
-    riscv_rom_copy_firmware_info(machine, rom_base, rom_size, sizeof(reset_vec),
+    riscv_rom_copy_firmware_info(machine, harts,
+                                 rom_base, rom_size,
+                                 sizeof(reset_vec),
                                  kernel_entry);
 }
 
diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index af5f923f54..5010c3eadb 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -646,7 +646,8 @@ static void sifive_u_machine_init(MachineState *machine)
     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
                           memmap[SIFIVE_U_DEV_MROM].base, &address_space_memory);
 
-    riscv_rom_copy_firmware_info(machine, memmap[SIFIVE_U_DEV_MROM].base,
+    riscv_rom_copy_firmware_info(machine, &s->soc.u_cpus,
+                                 memmap[SIFIVE_U_DEV_MROM].base,
                                  memmap[SIFIVE_U_DEV_MROM].size,
                                  sizeof(reset_vec), kernel_entry);
 
diff --git a/include/hw/riscv/boot.h b/include/hw/riscv/boot.h
index a2e4ae9cb0..806256d23f 100644
--- a/include/hw/riscv/boot.h
+++ b/include/hw/riscv/boot.h
@@ -56,7 +56,9 @@ void riscv_setup_rom_reset_vec(MachineState *machine, RISCVHartArrayState *harts
                                hwaddr rom_base, hwaddr rom_size,
                                uint64_t kernel_entry,
                                uint64_t fdt_load_addr);
-void riscv_rom_copy_firmware_info(MachineState *machine, hwaddr rom_base,
+void riscv_rom_copy_firmware_info(MachineState *machine,
+                                  RISCVHartArrayState *harts,
+                                  hwaddr rom_base,
                                   hwaddr rom_size,
                                   uint32_t reset_vec_size,
                                   uint64_t kernel_entry);
diff --git a/include/hw/riscv/boot_opensbi.h b/include/hw/riscv/boot_opensbi.h
index 1b749663dc..18664a174b 100644
--- a/include/hw/riscv/boot_opensbi.h
+++ b/include/hw/riscv/boot_opensbi.h
@@ -58,4 +58,33 @@ struct fw_dynamic_info {
     target_long boot_hart;
 };
 
+/** Representation dynamic info passed by previous booting stage */
+struct fw_dynamic_info32 {
+    /** Info magic */
+    int32_t magic;
+    /** Info version */
+    int32_t version;
+    /** Next booting stage address */
+    int32_t next_addr;
+    /** Next booting stage mode */
+    int32_t next_mode;
+    /** Options for OpenSBI library */
+    int32_t options;
+    /**
+     * Preferred boot HART id
+     *
+     * It is possible that the previous booting stage uses same link
+     * address as the FW_DYNAMIC firmware. In this case, the relocation
+     * lottery mechanism can potentially overwrite the previous booting
+     * stage while other HARTs are still running in the previous booting
+     * stage leading to boot-time crash. To avoid this boot-time crash,
+     * the previous booting stage can specify last HART that will jump
+     * to the FW_DYNAMIC firmware as the preferred boot HART.
+     *
+     * To avoid specifying a preferred boot HART, the previous booting
+     * stage can set it to -1UL which will force the FW_DYNAMIC firmware
+     * to use the relocation lottery mechanism.
+     */
+    int32_t boot_hart;
+};
 #endif
-- 
2.25.1