Real-time kernels such as RTEMS or Zephyr may use a static device tree
built into the kernel image. Do not require to use the -dtb option if
-kernel is used for the microchip-icicle-kit machine.
Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
---
hw/riscv/microchip_pfsoc.c | 53 ++++++++++++++++++--------------------
1 file changed, 25 insertions(+), 28 deletions(-)
diff --git a/hw/riscv/microchip_pfsoc.c b/hw/riscv/microchip_pfsoc.c
index 2ddc3464bb..f9e256df52 100644
--- a/hw/riscv/microchip_pfsoc.c
+++ b/hw/riscv/microchip_pfsoc.c
@@ -516,7 +516,6 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
uint64_t mem_low_size, mem_high_size;
hwaddr firmware_load_addr;
const char *firmware_name;
- bool kernel_as_payload = false;
target_ulong firmware_end_addr, kernel_start_addr;
uint64_t kernel_entry;
uint64_t fdt_load_addr;
@@ -589,25 +588,12 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
*
* This ensures backwards compatibility with how we used to expose -bios
* to users but allows them to run through direct kernel booting as well.
- *
- * When -kernel is used for direct boot, -dtb must be present to provide
- * a valid device tree for the board, as we don't generate device tree.
*/
- if (machine->kernel_filename && machine->dtb) {
- int fdt_size;
- machine->fdt = load_device_tree(machine->dtb, &fdt_size);
- if (!machine->fdt) {
- error_report("load_device_tree() failed");
- exit(1);
- }
-
+ if (machine->kernel_filename) {
firmware_name = RISCV64_BIOS_BIN;
firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
- kernel_as_payload = true;
- }
-
- if (!kernel_as_payload) {
+ } else {
firmware_name = BIOS_FILENAME;
firmware_load_addr = RESET_VECTOR;
}
@@ -617,7 +603,7 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
&firmware_load_addr, NULL);
riscv_boot_info_init(&boot_info, &s->soc.u_cpus);
- if (kernel_as_payload) {
+ if (machine->kernel_filename) {
kernel_start_addr = riscv_calc_kernel_start_addr(&boot_info,
firmware_end_addr);
@@ -625,19 +611,30 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
true, NULL);
kernel_entry = boot_info.image_low_addr;
- /* Compute the fdt load address in dram */
- hwaddr kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
- hwaddr kernel_ram_size = memmap[MICROCHIP_PFSOC_DRAM_LO].size;
-
- if (kernel_entry - kernel_ram_base >= kernel_ram_size) {
- kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_HI].base;
- kernel_ram_size = mem_high_size;
+ if (machine->dtb) {
+ int fdt_size;
+ machine->fdt = load_device_tree(machine->dtb, &fdt_size);
+ if (!machine->fdt) {
+ error_report("load_device_tree() failed");
+ exit(1);
+ }
+
+ /* Compute the FDT load address in DRAM */
+ hwaddr kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
+ hwaddr kernel_ram_size = memmap[MICROCHIP_PFSOC_DRAM_LO].size;
+
+ if (kernel_entry - kernel_ram_base >= kernel_ram_size) {
+ kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_HI].base;
+ kernel_ram_size = mem_high_size;
+ }
+
+ fdt_load_addr = riscv_compute_fdt_addr(kernel_ram_base, kernel_ram_size,
+ machine, &boot_info);
+ riscv_load_fdt(fdt_load_addr, machine->fdt);
+ } else {
+ fdt_load_addr = 0;
}
- fdt_load_addr = riscv_compute_fdt_addr(kernel_ram_base, kernel_ram_size,
- machine, &boot_info);
- riscv_load_fdt(fdt_load_addr, machine->fdt);
-
/* Load the reset vector */
riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, firmware_load_addr,
memmap[MICROCHIP_PFSOC_ENVM_DATA].base,
--
2.43.0On Fri, Feb 14, 2025 at 4:27 PM Sebastian Huber
<sebastian.huber@embedded-brains.de> wrote:
>
> Real-time kernels such as RTEMS or Zephyr may use a static device tree
> built into the kernel image. Do not require to use the -dtb option if
> -kernel is used for the microchip-icicle-kit machine.
That's a fair point, but it might also confuse people who expect QEMU
to generate a DTB if they don't specify one.
This at least needs a documentation update, but a warning log might
also be warranted if no `-dtb` is supplied
Alistair
>
> Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
> ---
> hw/riscv/microchip_pfsoc.c | 53 ++++++++++++++++++--------------------
> 1 file changed, 25 insertions(+), 28 deletions(-)
>
> diff --git a/hw/riscv/microchip_pfsoc.c b/hw/riscv/microchip_pfsoc.c
> index 2ddc3464bb..f9e256df52 100644
> --- a/hw/riscv/microchip_pfsoc.c
> +++ b/hw/riscv/microchip_pfsoc.c
> @@ -516,7 +516,6 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
> uint64_t mem_low_size, mem_high_size;
> hwaddr firmware_load_addr;
> const char *firmware_name;
> - bool kernel_as_payload = false;
> target_ulong firmware_end_addr, kernel_start_addr;
> uint64_t kernel_entry;
> uint64_t fdt_load_addr;
> @@ -589,25 +588,12 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
> *
> * This ensures backwards compatibility with how we used to expose -bios
> * to users but allows them to run through direct kernel booting as well.
> - *
> - * When -kernel is used for direct boot, -dtb must be present to provide
> - * a valid device tree for the board, as we don't generate device tree.
> */
>
> - if (machine->kernel_filename && machine->dtb) {
> - int fdt_size;
> - machine->fdt = load_device_tree(machine->dtb, &fdt_size);
> - if (!machine->fdt) {
> - error_report("load_device_tree() failed");
> - exit(1);
> - }
> -
> + if (machine->kernel_filename) {
> firmware_name = RISCV64_BIOS_BIN;
> firmware_load_addr = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> - kernel_as_payload = true;
> - }
> -
> - if (!kernel_as_payload) {
> + } else {
> firmware_name = BIOS_FILENAME;
> firmware_load_addr = RESET_VECTOR;
> }
> @@ -617,7 +603,7 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
> &firmware_load_addr, NULL);
>
> riscv_boot_info_init(&boot_info, &s->soc.u_cpus);
> - if (kernel_as_payload) {
> + if (machine->kernel_filename) {
> kernel_start_addr = riscv_calc_kernel_start_addr(&boot_info,
> firmware_end_addr);
>
> @@ -625,19 +611,30 @@ static void microchip_icicle_kit_machine_init(MachineState *machine)
> true, NULL);
> kernel_entry = boot_info.image_low_addr;
>
> - /* Compute the fdt load address in dram */
> - hwaddr kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> - hwaddr kernel_ram_size = memmap[MICROCHIP_PFSOC_DRAM_LO].size;
> -
> - if (kernel_entry - kernel_ram_base >= kernel_ram_size) {
> - kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_HI].base;
> - kernel_ram_size = mem_high_size;
> + if (machine->dtb) {
> + int fdt_size;
> + machine->fdt = load_device_tree(machine->dtb, &fdt_size);
> + if (!machine->fdt) {
> + error_report("load_device_tree() failed");
> + exit(1);
> + }
> +
> + /* Compute the FDT load address in DRAM */
> + hwaddr kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_LO].base;
> + hwaddr kernel_ram_size = memmap[MICROCHIP_PFSOC_DRAM_LO].size;
> +
> + if (kernel_entry - kernel_ram_base >= kernel_ram_size) {
> + kernel_ram_base = memmap[MICROCHIP_PFSOC_DRAM_HI].base;
> + kernel_ram_size = mem_high_size;
> + }
> +
> + fdt_load_addr = riscv_compute_fdt_addr(kernel_ram_base, kernel_ram_size,
> + machine, &boot_info);
> + riscv_load_fdt(fdt_load_addr, machine->fdt);
> + } else {
> + fdt_load_addr = 0;
> }
>
> - fdt_load_addr = riscv_compute_fdt_addr(kernel_ram_base, kernel_ram_size,
> - machine, &boot_info);
> - riscv_load_fdt(fdt_load_addr, machine->fdt);
> -
> /* Load the reset vector */
> riscv_setup_rom_reset_vec(machine, &s->soc.u_cpus, firmware_load_addr,
> memmap[MICROCHIP_PFSOC_ENVM_DATA].base,
> --
> 2.43.0
>
>
----- Am 24. Feb 2025 um 6:22 schrieb Alistair Francis alistair23@gmail.com: > On Fri, Feb 14, 2025 at 4:27 PM Sebastian Huber > <sebastian.huber@embedded-brains.de> wrote: >> >> Real-time kernels such as RTEMS or Zephyr may use a static device tree >> built into the kernel image. Do not require to use the -dtb option if >> -kernel is used for the microchip-icicle-kit machine. > > That's a fair point, but it might also confuse people who expect QEMU > to generate a DTB if they don't specify one. > > This at least needs a documentation update, but a warning log might > also be warranted if no `-dtb` is supplied I will add a documentation update to: docs/system/riscv/microchip-icicle-kit.rst Should I change this patch to require "-dtb none" to select no DTB at all? -- embedded brains GmbH & Co. KG Herr Sebastian HUBER Dornierstr. 4 82178 Puchheim Germany email: sebastian.huber@embedded-brains.de phone: +49-89-18 94 741 - 16 fax: +49-89-18 94 741 - 08 Registergericht: Amtsgericht München Registernummer: HRB 157899 Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler Unsere Datenschutzerklärung finden Sie hier: https://embedded-brains.de/datenschutzerklaerung/
On Mon, Feb 24, 2025 at 3:43 PM Sebastian Huber <sebastian.huber@embedded-brains.de> wrote: > > ----- Am 24. Feb 2025 um 6:22 schrieb Alistair Francis alistair23@gmail.com: > > > On Fri, Feb 14, 2025 at 4:27 PM Sebastian Huber > > <sebastian.huber@embedded-brains.de> wrote: > >> > >> Real-time kernels such as RTEMS or Zephyr may use a static device tree > >> built into the kernel image. Do not require to use the -dtb option if > >> -kernel is used for the microchip-icicle-kit machine. > > > > That's a fair point, but it might also confuse people who expect QEMU > > to generate a DTB if they don't specify one. > > > > This at least needs a documentation update, but a warning log might > > also be warranted if no `-dtb` is supplied > > I will add a documentation update to: > > docs/system/riscv/microchip-icicle-kit.rst > > Should I change this patch to require "-dtb none" to select no DTB at all? I don't think so, generally not specifying something means that it won't be loaded (-bios is just odd for historical reasons). Maybe just a log warning like "The QEMU Icicle machine does not generate a device tree, so no device tree is being provided to the guest". It'll be a bit annoying for people who don't want to run Linux (like your case), but all other Linux class RISC-V boards provide a DTB, so it's a little confusing Alistair > > -- > embedded brains GmbH & Co. KG > Herr Sebastian HUBER > Dornierstr. 4 > 82178 Puchheim > Germany > email: sebastian.huber@embedded-brains.de > phone: +49-89-18 94 741 - 16 > fax: +49-89-18 94 741 - 08 > > Registergericht: Amtsgericht München > Registernummer: HRB 157899 > Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler > Unsere Datenschutzerklärung finden Sie hier: > https://embedded-brains.de/datenschutzerklaerung/
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