Re: [Qemu-devel] [PATCH v5 1/2] hw/arm: Add arm SBSA reference machine, skeleton part

[Peter Maydell]

On Fri, 7 Dec 2018 at 09:08, Hongbo Zhang <address@hidden> wrote:
>
> For the Aarch64, there is one machine 'virt', it is primarily meant to
> run on KVM and execute virtualization workloads, but we need an
> environment as faithful as possible to physical hardware, for supporting
> firmware and OS development for pysical Aarch64 machines.
>
> This patch introduces new machine type 'sbsa-ref' with main features:
>  - Based on 'virt' machine type.
>  - Re-designed memory map.
>  - CPU type cortex-a57.
>  - EL2 and EL3 are enabled.
>  - GIC version 3.
>  - System bus AHCI controller.
>  - System bus XHCI controller(TBD).
>  - CDROM and hard disc on AHCI bus.
>  - E1000E ethernet card on PCIE bus.
>  - VGA display adaptor on PCIE bus.
>  - No virtio deivces.
>  - No fw_cfg device.
>  - No ACPI table supplied.
>  - Only minimal device tree nodes.
>
> Arm Trusted Firmware and UEFI porting to this are done accordingly, and
> it should supply ACPI tables to load OS, the minimal device tree nodes
> supplied from this platform are only to pass the dynamic info reflecting
> command line input to firmware, not for loading OS.
>
> To make the review easier, this task is split into two patches, the
> fundamental sceleton part and the peripheral devices part, this patch is
> the first part.

Firstly, apologies for this having sat on my to-review queue for
so long...

> Signed-off-by: Hongbo Zhang <address@hidden>
> ---
>  hw/arm/Makefile.objs  |   2 +-
>  hw/arm/sbsa-ref.c     | 277 
> ++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/hw/arm/virt.h |   1 +
>  3 files changed, 279 insertions(+), 1 deletion(-)
>  create mode 100644 hw/arm/sbsa-ref.c
>
> diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs
> index d51fcec..a8895eb 100644
> --- a/hw/arm/Makefile.objs
> +++ b/hw/arm/Makefile.objs
> @@ -1,4 +1,4 @@
> -obj-y += boot.o virt.o sysbus-fdt.o
> +obj-y += boot.o virt.o sbsa-ref.o sysbus-fdt.o
>  obj-$(CONFIG_ACPI) += virt-acpi-build.o
>  obj-$(CONFIG_DIGIC) += digic_boards.o
>  obj-$(CONFIG_EXYNOS4) += exynos4_boards.o
> diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
> new file mode 100644
> index 0000000..1d6252b
> --- /dev/null
> +++ b/hw/arm/sbsa-ref.c
> @@ -0,0 +1,277 @@
> +/*
> + * ARM SBSA Reference Platform emulation
> + *
> + * Copyright (c) 2018 Linaro Limited
> + * Written by Hongbo Zhang <address@hidden>
> + *
> + * Based on hw/arm/virt.c
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2 or later, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License along 
> with
> + * this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "hw/arm/arm.h"
> +#include "hw/arm/virt.h"

This isn't the virt board, so I think it would be better if it did
not include the virt.h header or use structures/classes that are
private to the virt board. It should be its own thing.

> +#include "hw/devices.h"
> +#include "net/net.h"
> +#include "sysemu/device_tree.h"
> +#include "sysemu/numa.h"
> +#include "sysemu/sysemu.h"
> +#include "hw/loader.h"
> +#include "exec/address-spaces.h"
> +#include "qemu/error-report.h"
> +#include "hw/pci-host/gpex.h"
> +#include "hw/arm/sysbus-fdt.h"
> +#include "hw/arm/fdt.h"
> +#include "hw/intc/arm_gic.h"
> +#include "hw/intc/arm_gicv3_common.h"
> +#include "kvm_arm.h"
> +#include "hw/ide/internal.h"
> +#include "hw/ide/ahci_internal.h"
> +#include "qemu/units.h"
> +
> +#define NUM_IRQS 256
> +
> +#define RAMLIMIT_GB 8192
> +#define RAMLIMIT_BYTES (RAMLIMIT_GB * GiB)
> +
> +static const MemMapEntry sbsa_ref_memmap[] = {
> +    /* 512M boot ROM */
> +    [VIRT_FLASH] =              {          0, 0x20000000 },
> +    /* 512M secure memery */

"memory"

> +    [VIRT_SECURE_MEM] =         { 0x20000000, 0x20000000 },
> +    [VIRT_CPUPERIPHS] =         { 0x40000000, 0x00080000 },
> +    /* GIC distributor and CPU interface expansion spaces reserved */
> +    [VIRT_GIC_DIST] =           { 0x40000000, 0x00010000 },
> +    [VIRT_GIC_CPU] =            { 0x40040000, 0x00010000 },

If they're just reserved you don't really need to list them here,
as they're covered by the VIRT_CPUPERIPHS space anyway. (You
don't list the VIRT_GIC_HYP registers or VIRT_GIC_VCPU.)

> +    /* 64M redistributor space allows up to 512 CPUs */
> +    [VIRT_GIC_REDIST] =         { 0x40080000, 0x04000000 },
> +    /* Space here reserved for redistributor and vCPU/HYP expansion */
> +    [VIRT_UART] =               { 0x60000000, 0x00001000 },
> +    [VIRT_RTC] =                { 0x60010000, 0x00001000 },
> +    [VIRT_GPIO] =               { 0x60020000, 0x00001000 },
> +    [VIRT_SECURE_UART] =        { 0x60030000, 0x00001000 },
> +    [VIRT_SMMU] =               { 0x60040000, 0x00020000 },
> +    /* Space here reserved for more SMMUs */
> +    [VIRT_AHCI] =               { 0x60100000, 0x00010000 },
> +    /* Space here reserved for other devices */
> +    [VIRT_PCIE_PIO] =           { 0x7fff0000, 0x00010000 },
> +    /* 256M PCIE ECAM space */
> +    [VIRT_PCIE_ECAM] =          { 0x80000000, 0x10000000 },

Comment says 256M but the size field says it's larger...

> +    /* ~1TB for PCIE MMIO (4GB to 1024GB boundary) */
> +    [VIRT_PCIE_MMIO] =          { 0x100000000ULL, 0xFF00000000ULL },
> +    [VIRT_MEM] =                { 0x10000000000ULL, RAMLIMIT_BYTES },
> +};
> +
> +static const int sbsa_ref_irqmap[] = {
> +    [VIRT_UART] = 1,
> +    [VIRT_RTC] = 2,
> +    [VIRT_PCIE] = 3, /* ... to 6 */
> +    [VIRT_GPIO] = 7,
> +    [VIRT_SECURE_UART] = 8,
> +    [VIRT_AHCI] = 9,
> +};
> +
> +static void sbsa_ref_init(MachineState *machine)
> +{
> +    VirtMachineState *vms = VIRT_MACHINE(machine);

As noted above, I think it would be better to be your own
subclass of MachineState, rather than being a subclass of
the virt board. Is there anything that becomes particularly
awkward if you do it that way?

thanks
-- PMM