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[PATCH v2 4/6] hw/riscv: Allow direct start of kernel for MPFS

Sebastian Huber posted 6 patches 1 month, 1 week ago
There is a newer version of this series
[PATCH v2 4/6] hw/riscv: Allow direct start of kernel for MPFS
Posted by Sebastian Huber 1 month, 1 week ago 
Further customize the -bios and -kernel options behaviour for the
microchip-icicle-kit machine.  If "-bios none -kernel filename" is
specified, then do not load a firmware and instead only load and start
the kernel image.

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
---
 hw/riscv/microchip_pfsoc.c | 57 ++++++++++++++++++++++++++------------
 1 file changed, 40 insertions(+), 17 deletions(-)

diff --git a/hw/riscv/microchip_pfsoc.c b/hw/riscv/microchip_pfsoc.c
index 844dc0545c..df902c8667 100644
--- a/hw/riscv/microchip_pfsoc.c
+++ b/hw/riscv/microchip_pfsoc.c
@@ -578,29 +578,45 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
     }
 
     /*
-     * We follow the following table to select which payload we execute.
+     * We follow the following table to select which firmware we use.
      *
-     *  -bios |    -kernel | payload
-     * -------+------------+--------
-     *      N |          N | HSS
-     *      Y | don't care | HSS
-     *      N |          Y | kernel
-     *
-     * This ensures backwards compatibility with how we used to expose -bios
-     * to users but allows them to run through direct kernel booting as well.
+     * -bios         | -kernel    | firmware
+     * --------------+------------+--------
+     * none          |          N | error
+     * none          |          Y | kernel
+     * NULL, default |          N | BIOS_FILENAME
+     * NULL, default |          Y | RISCV64_BIOS_BIN
+     * other         | don't care | other
      */
+    if (machine->firmware && !strcmp(machine->firmware, "none")) {
+        if (!machine->kernel_filename) {
+            error_report("for -bios none, a kernel is required");
+            exit(1);
+        }
 
-    if (machine->kernel_filename) {
-        firmware_name = RISCV64_BIOS_BIN;
-        firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
+        firmware_name = NULL;
+        firmware_load_addr = RESET_VECTOR;
+    } else if (!machine->firmware || !strcmp(machine->firmware, "default")) {
+        if (machine->kernel_filename) {
+            firmware_name = RISCV64_BIOS_BIN;
+            firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
+        } else {
+            firmware_name = BIOS_FILENAME;
+            firmware_load_addr = RESET_VECTOR;
+        }
     } else {
-        firmware_name = BIOS_FILENAME;
+        firmware_name = machine->firmware;
         firmware_load_addr = RESET_VECTOR;
     }
 
-    /* Load the firmware */
-    firmware_end_addr = riscv_find_and_load_firmware(machine, firmware_name,
-                                                     &firmware_load_addr, NULL);
+    /* Load the firmware if necessary */
+    if (firmware_name) {
+        const char *filename = riscv_find_firmware(firmware_name, NULL);
+        firmware_end_addr = riscv_load_firmware(filename, &firmware_load_addr,
+                                                NULL);
+    } else {
+        firmware_end_addr = firmware_load_addr;
+    }
 
     riscv_boot_info_init(&boot_info, &s->soc.u_cpus);
     if (machine->kernel_filename) {
@@ -638,8 +654,15 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
             fdt_load_addr = 0;
         }
 
+        hwaddr start_addr;
+        if (firmware_name) {
+            start_addr = firmware_load_addr;
+        } else {
+            start_addr = kernel_entry;
+        }
+
         /* Load the reset vector */
-        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, firmware_load_addr,
+        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, start_addr,
                                   memmap[MICROCHIP_PFSOC_ENVM_DATA].base,
                                   memmap[MICROCHIP_PFSOC_ENVM_DATA].size,
                                   kernel_entry, fdt_load_addr);
-- 
2.43.0
Re: [PATCH v2 4/6] hw/riscv: Allow direct start of kernel for MPFS
Posted by Daniel Henrique Barboza 2 weeks, 6 days ago 
Hi,

On 2/24/25 9:54 PM, Sebastian Huber wrote:
> Further customize the -bios and -kernel options behaviour for the
> microchip-icicle-kit machine.  If "-bios none -kernel filename" is
> specified, then do not load a firmware and instead only load and start
> the kernel image.
> 
> Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
> ---
>   hw/riscv/microchip_pfsoc.c | 57 ++++++++++++++++++++++++++------------
>   1 file changed, 40 insertions(+), 17 deletions(-)
> 
> diff --git a/hw/riscv/microchip_pfsoc.c b/hw/riscv/microchip_pfsoc.c
> index 844dc0545c..df902c8667 100644
> --- a/hw/riscv/microchip_pfsoc.c
> +++ b/hw/riscv/microchip_pfsoc.c
> @@ -578,29 +578,45 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
>       }
>   
>       /*
> -     * We follow the following table to select which payload we execute.
> +     * We follow the following table to select which firmware we use.
>        *
> -     *  -bios |    -kernel | payload
> -     * -------+------------+--------
> -     *      N |          N | HSS
> -     *      Y | don't care | HSS
> -     *      N |          Y | kernel
> -     *
> -     * This ensures backwards compatibility with how we used to expose -bios
> -     * to users but allows them to run through direct kernel booting as well.
> +     * -bios         | -kernel    | firmware
> +     * --------------+------------+--------
> +     * none          |          N | error
> +     * none          |          Y | kernel
> +     * NULL, default |          N | BIOS_FILENAME


This change is breaking the following test:

---------

$ QTEST_QEMU_BINARY=./build/qemu-system-riscv64 ./build/tests/qtest/qom-test
(...)
# slow test /riscv64/qom/amd-microblaze-v-generic executed in 2.28 secs
# starting QEMU: exec ./build/qemu-system-riscv64 -qtest unix:/tmp/qtest-1361875.sock -qtest-log /dev/null -chardev socket,path=/tmp/qtest-1361875.qmp,id=char0 -mon chardev=char0,mode=control -display none -audio none -machine microchip-icicle-kit -accel qtest
**
ERROR:../hw/riscv/boot.c:164:riscv_load_firmware: assertion failed: (firmware_filename != NULL)
Bail out! ERROR:../hw/riscv/boot.c:164:riscv_load_firmware: assertion failed: (firmware_filename != NULL)
Broken pipe

---------

The reason is that, with the default machine settings (no -bios and no -kernel
options), firmware_name is now defaulted to BIOS_FILENAME (hss.bin). But we're not
distributing 'hss.bin' in pc-bios:

$ ls pc-bios/ |  grep hss
$

Then, in the following code, 'filename' will be NULL and riscv_load_firmware() will
g_assert():


> +    if (firmware_name) {
> +        const char *filename = riscv_find_firmware(firmware_name, NULL);
> +        firmware_end_addr = riscv_load_firmware(filename, &firmware_load_addr,
> +                                                NULL);
> +    }


Possible solutions:

- package hss.bin in QEMU so it can be used as a default firmware;

- redo the logic to allow the board to run (even if inactive) with absent
-bios and -kernel to allow QEMU model tests to run.



Thanks,

Daniel

> +     * NULL, default |          Y | RISCV64_BIOS_BIN
> +     * other         | don't care | other
>        */
> +    if (machine->firmware && !strcmp(machine->firmware, "none")) {
> +        if (!machine->kernel_filename) {
> +            error_report("for -bios none, a kernel is required");
> +            exit(1);
> +        }
>   
> -    if (machine->kernel_filename) {
> -        firmware_name = RISCV64_BIOS_BIN;
> -        firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> +        firmware_name = NULL;
> +        firmware_load_addr = RESET_VECTOR;
> +    } else if (!machine->firmware || !strcmp(machine->firmware, "default")) {
> +        if (machine->kernel_filename) {
> +            firmware_name = RISCV64_BIOS_BIN;
> +            firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> +        } else {
> +            firmware_name = BIOS_FILENAME;
> +            firmware_load_addr = RESET_VECTOR;
> +        }
>       } else {
> -        firmware_name = BIOS_FILENAME;
> +        firmware_name = machine->firmware;
>           firmware_load_addr = RESET_VECTOR;
>       }
>   
> -    /* Load the firmware */
> -    firmware_end_addr = riscv_find_and_load_firmware(machine, firmware_name,
> -                                                     &firmware_load_addr, NULL);
> +    /* Load the firmware if necessary */
> +    if (firmware_name) {
> +        const char *filename = riscv_find_firmware(firmware_name, NULL);
> +        firmware_end_addr = riscv_load_firmware(filename, &firmware_load_addr,
> +                                                NULL);
> +    } else {
> +        firmware_end_addr = firmware_load_addr;
> +    }
>   
>       riscv_boot_info_init(&boot_info, &s->soc.u_cpus);
>       if (machine->kernel_filename) {
> @@ -638,8 +654,15 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
>               fdt_load_addr = 0;
>           }
>   
> +        hwaddr start_addr;
> +        if (firmware_name) {
> +            start_addr = firmware_load_addr;
> +        } else {
> +            start_addr = kernel_entry;
> +        }
> +
>           /* Load the reset vector */
> -        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, firmware_load_addr,
> +        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, start_addr,
>                                     memmap[MICROCHIP_PFSOC_ENVM_DATA].base,
>                                     memmap[MICROCHIP_PFSOC_ENVM_DATA].size,
>                                     kernel_entry, fdt_load_addr);
Re: [PATCH v2 4/6] hw/riscv: Allow direct start of kernel for MPFS
Posted by Alistair Francis 4 weeks ago 
On Tue, Feb 25, 2025 at 10:55 AM Sebastian Huber
<sebastian.huber@embedded-brains.de> wrote:
>
> Further customize the -bios and -kernel options behaviour for the
> microchip-icicle-kit machine.  If "-bios none -kernel filename" is
> specified, then do not load a firmware and instead only load and start
> the kernel image.
>
> Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/riscv/microchip_pfsoc.c | 57 ++++++++++++++++++++++++++------------
>  1 file changed, 40 insertions(+), 17 deletions(-)
>
> diff --git a/hw/riscv/microchip_pfsoc.c b/hw/riscv/microchip_pfsoc.c
> index 844dc0545c..df902c8667 100644
> --- a/hw/riscv/microchip_pfsoc.c
> +++ b/hw/riscv/microchip_pfsoc.c
> @@ -578,29 +578,45 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
>      }
>
>      /*
> -     * We follow the following table to select which payload we execute.
> +     * We follow the following table to select which firmware we use.
>       *
> -     *  -bios |    -kernel | payload
> -     * -------+------------+--------
> -     *      N |          N | HSS
> -     *      Y | don't care | HSS
> -     *      N |          Y | kernel
> -     *
> -     * This ensures backwards compatibility with how we used to expose -bios
> -     * to users but allows them to run through direct kernel booting as well.
> +     * -bios         | -kernel    | firmware
> +     * --------------+------------+--------
> +     * none          |          N | error
> +     * none          |          Y | kernel
> +     * NULL, default |          N | BIOS_FILENAME
> +     * NULL, default |          Y | RISCV64_BIOS_BIN
> +     * other         | don't care | other
>       */
> +    if (machine->firmware && !strcmp(machine->firmware, "none")) {
> +        if (!machine->kernel_filename) {
> +            error_report("for -bios none, a kernel is required");
> +            exit(1);
> +        }
>
> -    if (machine->kernel_filename) {
> -        firmware_name = RISCV64_BIOS_BIN;
> -        firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> +        firmware_name = NULL;
> +        firmware_load_addr = RESET_VECTOR;
> +    } else if (!machine->firmware || !strcmp(machine->firmware, "default")) {
> +        if (machine->kernel_filename) {
> +            firmware_name = RISCV64_BIOS_BIN;
> +            firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> +        } else {
> +            firmware_name = BIOS_FILENAME;
> +            firmware_load_addr = RESET_VECTOR;
> +        }
>      } else {
> -        firmware_name = BIOS_FILENAME;
> +        firmware_name = machine->firmware;
>          firmware_load_addr = RESET_VECTOR;
>      }
>
> -    /* Load the firmware */
> -    firmware_end_addr = riscv_find_and_load_firmware(machine, firmware_name,
> -                                                     &firmware_load_addr, NULL);
> +    /* Load the firmware if necessary */
> +    if (firmware_name) {
> +        const char *filename = riscv_find_firmware(firmware_name, NULL);
> +        firmware_end_addr = riscv_load_firmware(filename, &firmware_load_addr,
> +                                                NULL);
> +    } else {
> +        firmware_end_addr = firmware_load_addr;
> +    }
>
>      riscv_boot_info_init(&boot_info, &s->soc.u_cpus);
>      if (machine->kernel_filename) {
> @@ -638,8 +654,15 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
>              fdt_load_addr = 0;
>          }
>
> +        hwaddr start_addr;
> +        if (firmware_name) {
> +            start_addr = firmware_load_addr;
> +        } else {
> +            start_addr = kernel_entry;
> +        }
> +
>          /* Load the reset vector */
> -        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, firmware_load_addr,
> +        riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, start_addr,
>                                    memmap[MICROCHIP_PFSOC_ENVM_DATA].base,
>                                    memmap[MICROCHIP_PFSOC_ENVM_DATA].size,
>                                    kernel_entry, fdt_load_addr);
> --
> 2.43.0
>

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