hw/riscv: Load the kernel after the firmware

Instead of loading the kernel at a hardcoded start address, let's load
the kernel at the next aligned address after the end of the firmware.

This should have no impact for current users of OpenSBI, but will
allow loading a noMMU kernel at the start of memory.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Tested-by: Bin Meng <bin.meng@windriver.com>
Message-id: 46c00c4f15b42feb792090e3d74359e180a6d954.1602634524.git.alistair.francis@wdc.com

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index 5dea644f475ce89993e27f709c1ef363768a64b5..9b3fe3fb1e0fdd3431f6c6ef7f2122dda624e185 100644 (file)
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -33,10 +33,8 @@
 #include <libfdt.h>
 
 #if defined(TARGET_RISCV32)
-# define KERNEL_BOOT_ADDRESS 0x80400000
 #define fw_dynamic_info_data(__val)     cpu_to_le32(__val)
 #else
-# define KERNEL_BOOT_ADDRESS 0x80200000
 #define fw_dynamic_info_data(__val)     cpu_to_le64(__val)
 #endif
 
@@ -49,6 +47,15 @@ bool riscv_is_32_bit(MachineState *machine)
     }
 }
 
+target_ulong riscv_calc_kernel_start_addr(MachineState *machine,
+                                          target_ulong firmware_end_addr) {
+    if (riscv_is_32_bit(machine)) {
+        return QEMU_ALIGN_UP(firmware_end_addr, 4 * MiB);
+    } else {
+        return QEMU_ALIGN_UP(firmware_end_addr, 2 * MiB);
+    }
+}
+
 target_ulong riscv_find_and_load_firmware(MachineState *machine,
                                           const char *default_machine_firmware,
                                           hwaddr firmware_load_addr,
@@ -123,7 +130,9 @@ target_ulong riscv_load_firmware(const char *firmware_filename,
     exit(1);
 }
 
-target_ulong riscv_load_kernel(const char *kernel_filename, symbol_fn_t sym_cb)
+target_ulong riscv_load_kernel(const char *kernel_filename,
+                               target_ulong kernel_start_addr,
+                               symbol_fn_t sym_cb)
 {
     uint64_t kernel_entry;
 
@@ -138,9 +147,9 @@ target_ulong riscv_load_kernel(const char *kernel_filename, symbol_fn_t sym_cb)
         return kernel_entry;
     }
 
-    if (load_image_targphys_as(kernel_filename, KERNEL_BOOT_ADDRESS,
+    if (load_image_targphys_as(kernel_filename, kernel_start_addr,
                                ram_size, NULL) > 0) {
-        return KERNEL_BOOT_ADDRESS;
+        return kernel_start_addr;
     }
 
     error_report("could not load kernel '%s'", kernel_filename);

diff --git a/hw/riscv/opentitan.c b/hw/riscv/opentitan.c
index 0531bd879b3022816daba499a6b64a7c73ff244c..cc758b78b881a7c5b23c4a84d43b5c111d65e72e 100644 (file)
--- a/hw/riscv/opentitan.c
+++ b/hw/riscv/opentitan.c
@@ -75,7 +75,8 @@ static void opentitan_board_init(MachineState *machine)
     }
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename, NULL);
+        riscv_load_kernel(machine->kernel_filename,
+                          memmap[IBEX_DEV_RAM].base, NULL);
     }
 }
 

diff --git a/hw/riscv/sifive_e.c b/hw/riscv/sifive_e.c
index fcfac168161beeb7cabc87171ff5eef8dc634313..59bac4cc9ad5125b5fb25eae7db73696136099e6 100644 (file)
--- a/hw/riscv/sifive_e.c
+++ b/hw/riscv/sifive_e.c
@@ -114,7 +114,8 @@ static void sifive_e_machine_init(MachineState *machine)
                           memmap[SIFIVE_E_DEV_MROM].base, &address_space_memory);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename, NULL);
+        riscv_load_kernel(machine->kernel_filename,
+                          memmap[SIFIVE_E_DEV_DTIM].base, NULL);
     }
 }
 

diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 5f3ad9bc0fbd044f89eb3afb416e5f0c9969b81d..b2472c662748d7eecb565bda09fc0affd67b58da 100644 (file)
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -415,6 +415,7 @@ static void sifive_u_machine_init(MachineState *machine)
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
     MemoryRegion *flash0 = g_new(MemoryRegion, 1);
     target_ulong start_addr = memmap[SIFIVE_U_DEV_DRAM].base;
+    target_ulong firmware_end_addr, kernel_start_addr;
     uint32_t start_addr_hi32 = 0x00000000;
     int i;
     uint32_t fdt_load_addr;
@@ -474,10 +475,15 @@ static void sifive_u_machine_init(MachineState *machine)
         break;
     }
 
-    riscv_find_and_load_firmware(machine, BIOS_FILENAME, start_addr, NULL);
+    firmware_end_addr = riscv_find_and_load_firmware(machine, BIOS_FILENAME,
+                                                     start_addr, NULL);
 
     if (machine->kernel_filename) {
-        kernel_entry = riscv_load_kernel(machine->kernel_filename, NULL);
+        kernel_start_addr = riscv_calc_kernel_start_addr(machine,
+                                                         firmware_end_addr);
+
+        kernel_entry = riscv_load_kernel(machine->kernel_filename,
+                                         kernel_start_addr, NULL);
 
         if (machine->initrd_filename) {
             hwaddr start;

diff --git a/hw/riscv/spike.c b/hw/riscv/spike.c
index 3fd152a035afc8a15a2431b665853861fe70cc3d..facac6e7d2d7491b54504b0c72d1b8b6d98802a8 100644 (file)
--- a/hw/riscv/spike.c
+++ b/hw/riscv/spike.c
@@ -195,6 +195,7 @@ static void spike_board_init(MachineState *machine)
     MemoryRegion *system_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
     MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
+    target_ulong firmware_end_addr, kernel_start_addr;
     uint32_t fdt_load_addr;
     uint64_t kernel_entry;
     char *soc_name;
@@ -261,12 +262,16 @@ static void spike_board_init(MachineState *machine)
     memory_region_add_subregion(system_memory, memmap[SPIKE_MROM].base,
                                 mask_rom);
 
-    riscv_find_and_load_firmware(machine, BIOS_FILENAME,
-                                 memmap[SPIKE_DRAM].base,
-                                 htif_symbol_callback);
+    firmware_end_addr = riscv_find_and_load_firmware(machine, BIOS_FILENAME,
+                                                     memmap[SPIKE_DRAM].base,
+                                                     htif_symbol_callback);
 
     if (machine->kernel_filename) {
+        kernel_start_addr = riscv_calc_kernel_start_addr(machine,
+                                                         firmware_end_addr);
+
         kernel_entry = riscv_load_kernel(machine->kernel_filename,
+                                         kernel_start_addr,
                                          htif_symbol_callback);
 
         if (machine->initrd_filename) {

diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 41bd2f38ba181a6178485efe8493c3ff9b884f98..6bfd10dfc706ef2b90bb12583ba480267be03340 100644 (file)
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -493,6 +493,7 @@ static void virt_machine_init(MachineState *machine)
     char *plic_hart_config, *soc_name;
     size_t plic_hart_config_len;
     target_ulong start_addr = memmap[VIRT_DRAM].base;
+    target_ulong firmware_end_addr, kernel_start_addr;
     uint32_t fdt_load_addr;
     uint64_t kernel_entry;
     DeviceState *mmio_plic, *virtio_plic, *pcie_plic;
@@ -602,11 +603,15 @@ static void virt_machine_init(MachineState *machine)
     memory_region_add_subregion(system_memory, memmap[VIRT_MROM].base,
                                 mask_rom);
 
-    riscv_find_and_load_firmware(machine, BIOS_FILENAME,
-                                 memmap[VIRT_DRAM].base, NULL);
+    firmware_end_addr = riscv_find_and_load_firmware(machine, BIOS_FILENAME,
+                                                     start_addr, NULL);
 
     if (machine->kernel_filename) {
-        kernel_entry = riscv_load_kernel(machine->kernel_filename, NULL);
+        kernel_start_addr = riscv_calc_kernel_start_addr(machine,
+                                                         firmware_end_addr);
+
+        kernel_entry = riscv_load_kernel(machine->kernel_filename,
+                                         kernel_start_addr, NULL);
 
         if (machine->initrd_filename) {
             hwaddr start;

diff --git a/include/hw/riscv/boot.h b/include/hw/riscv/boot.h
index 2975ed1a31d5cbcecf9591beff8429cd1ebbfcf5..0b019887274da86cfc6ce6da713bf396df0e2553 100644 (file)
--- a/include/hw/riscv/boot.h
+++ b/include/hw/riscv/boot.h
@@ -25,6 +25,8 @@
 
 bool riscv_is_32_bit(MachineState *machine);
 
+target_ulong riscv_calc_kernel_start_addr(MachineState *machine,
+                                          target_ulong firmware_end_addr);
 target_ulong riscv_find_and_load_firmware(MachineState *machine,
                                           const char *default_machine_firmware,
                                           hwaddr firmware_load_addr,
@@ -34,6 +36,7 @@ target_ulong riscv_load_firmware(const char *firmware_filename,
                                  hwaddr firmware_load_addr,
                                  symbol_fn_t sym_cb);
 target_ulong riscv_load_kernel(const char *kernel_filename,
+                               target_ulong firmware_end_addr,
                                symbol_fn_t sym_cb);
 hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
                          uint64_t kernel_entry, hwaddr *start);