On 10/03/2022 11:27, Richard Henderson wrote:
> From: Amir Gonnen <amir.gonnen@neuroblade.ai>
>
> Demonstrate how to use nios2 VIC on a machine.
> Introduce a new machine property to attach a VIC.
>
> When VIC is present, let the CPU know that it should use the
> External Interrupt Interface instead of the Internal Interrupt Interface.
> The devices on the machine are attached to the VIC and not directly to cpu.
> To allow VIC update EIC fields, we set the "cpu" property of the VIC
> with a reference to the nios2 cpu.
>
> Signed-off-by: Amir Gonnen <amir.gonnen@neuroblade.ai>
> Message-Id: <20220303153906.2024748-6-amir.gonnen@neuroblade.ai>
> [rth: Put a property on the 10m50-ghrd machine, rather than
> create a new machine class.]
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> hw/nios2/10m50_devboard.c | 61 +++++++++++++++++++++++++++++++++------
> hw/nios2/Kconfig | 1 +
> 2 files changed, 53 insertions(+), 9 deletions(-)
>
> diff --git a/hw/nios2/10m50_devboard.c b/hw/nios2/10m50_devboard.c
> index dda4ab2bf5..91383fb097 100644
> --- a/hw/nios2/10m50_devboard.c
> +++ b/hw/nios2/10m50_devboard.c
> @@ -27,6 +27,7 @@
>
> #include "hw/sysbus.h"
> #include "hw/char/serial.h"
> +#include "hw/intc/nios2_vic.h"
> #include "hw/qdev-properties.h"
> #include "sysemu/sysemu.h"
> #include "hw/boards.h"
> @@ -43,6 +44,8 @@ struct Nios2MachineState {
> MemoryRegion phys_tcm_alias;
> MemoryRegion phys_ram;
> MemoryRegion phys_ram_alias;
> +
> + bool vic;
> };
>
> #define TYPE_NIOS2_MACHINE MACHINE_TYPE_NAME("10m50-ghrd")
> @@ -81,10 +84,39 @@ static void nios2_10m50_ghrd_init(MachineState *machine)
> memory_region_add_subregion(address_space_mem, 0xc0000000 + ram_base,
> &nms->phys_ram_alias);
>
> - /* Create CPU -- FIXME */
> - cpu = NIOS2_CPU(cpu_create(TYPE_NIOS2_CPU));
> - for (i = 0; i < 32; i++) {
> - irq[i] = qdev_get_gpio_in_named(DEVICE(cpu), "IRQ", i);
> + /* Create CPU. We need to set eic_present between init and realize. */
> + cpu = NIOS2_CPU(object_new(TYPE_NIOS2_CPU));
> +
> + /* Enable the External Interrupt Controller within the CPU. */
> + cpu->eic_present = nms->vic;
> +
> + /* Configure new exception vectors. */
> + cpu->reset_addr = 0xd4000000;
> + cpu->exception_addr = 0xc8000120;
> + cpu->fast_tlb_miss_addr = 0xc0000100;
> +
> + qdev_realize_and_unref(DEVICE(cpu), NULL, &error_fatal);
> +
> + if (nms->vic) {
> + DeviceState *dev = qdev_new(TYPE_NIOS2_VIC);
> + MemoryRegion *dev_mr;
> + qemu_irq cpu_irq;
> +
> + object_property_set_link(OBJECT(dev), "cpu", OBJECT(cpu), &error_fatal);
> + sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> +
> + cpu_irq = qdev_get_gpio_in_named(DEVICE(cpu), "EIC", 0);
> + sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, cpu_irq);
> + for (int i = 0; i < 32; i++) {
> + irq[i] = qdev_get_gpio_in(dev, i);
> + }
> +
> + dev_mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0);
> + memory_region_add_subregion(address_space_mem, 0x18002000, dev_mr);
> + } else {
> + for (i = 0; i < 32; i++) {
> + irq[i] = qdev_get_gpio_in_named(DEVICE(cpu), "IRQ", i);
> + }
> }
>
> /* Register: Altera 16550 UART */
> @@ -105,15 +137,22 @@ static void nios2_10m50_ghrd_init(MachineState *machine)
> sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0xe0000880);
> sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq[5]);
>
> - /* Configure new exception vectors and reset CPU for it to take effect. */
> - cpu->reset_addr = 0xd4000000;
> - cpu->exception_addr = 0xc8000120;
> - cpu->fast_tlb_miss_addr = 0xc0000100;
> -
> nios2_load_kernel(cpu, ram_base, ram_size, machine->initrd_filename,
> BINARY_DEVICE_TREE_FILE, NULL);
> }
>
> +static bool get_vic(Object *obj, Error **errp)
> +{
> + Nios2MachineState *nms = NIOS2_MACHINE(obj);
> + return nms->vic;
> +}
> +
> +static void set_vic(Object *obj, bool value, Error **errp)
> +{
> + Nios2MachineState *nms = NIOS2_MACHINE(obj);
> + nms->vic = value;
> +}
> +
> static void nios2_10m50_ghrd_class_init(ObjectClass *oc, void *data)
> {
> MachineClass *mc = MACHINE_CLASS(oc);
> @@ -121,6 +160,10 @@ static void nios2_10m50_ghrd_class_init(ObjectClass *oc, void *data)
> mc->desc = "Altera 10M50 GHRD Nios II design";
> mc->init = nios2_10m50_ghrd_init;
> mc->is_default = true;
> +
> + object_class_property_add_bool(oc, "vic", get_vic, set_vic);
> + object_class_property_set_description(oc, "vic",
> + "Set on/off to enable/disable the Vectored Interrupt Controller");
> }
>
> static const TypeInfo nios2_10m50_ghrd_type_info = {
> diff --git a/hw/nios2/Kconfig b/hw/nios2/Kconfig
> index b10ea640da..4748ae27b6 100644
> --- a/hw/nios2/Kconfig
> +++ b/hw/nios2/Kconfig
> @@ -3,6 +3,7 @@ config NIOS2_10M50
> select NIOS2
> select SERIAL
> select ALTERA_TIMER
> + select NIOS2_VIC
>
> config NIOS2_GENERIC_NOMMU
> bool
I'm surprised that there isn't a way to remove the boiler-plate code around setting
the bool "vic" property (when compared with qdev), but regardless:
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
ATB,
Mark.