* [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI
@ 2016-01-15 14:11 Shannon Zhao
2016-01-15 14:18 ` Andrew Jones
2016-01-15 14:53 ` Peter Maydell
0 siblings, 2 replies; 3+ messages in thread
From: Shannon Zhao @ 2016-01-15 14:11 UTC (permalink / raw)
To: qemu-arm
Cc: peter.maydell, ard.biesheuvel, edk2-devel, qemu-devel,
zhaoshenglong, lersek
When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
While UEFI can use libfdt to disable the RTC device node in the DTB that
it passes to the OS, it cannot modify AML. Therefore, we won't generate
the RTC ACPI device at all when using UEFI.
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
---
V3: add comments to explain why it doesn't generate RTC ACPI device
---
hw/arm/virt-acpi-build.c | 24 +++++-------------------
1 file changed, 5 insertions(+), 19 deletions(-)
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 0caf5ce..0d5c635 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -94,23 +94,6 @@ static void acpi_dsdt_add_uart(Aml *scope, const MemMapEntry *uart_memmap,
aml_append(scope, dev);
}
-static void acpi_dsdt_add_rtc(Aml *scope, const MemMapEntry *rtc_memmap,
- uint32_t rtc_irq)
-{
- Aml *dev = aml_device("RTC0");
- aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0013")));
- aml_append(dev, aml_name_decl("_UID", aml_int(0)));
-
- Aml *crs = aml_resource_template();
- aml_append(crs, aml_memory32_fixed(rtc_memmap->base,
- rtc_memmap->size, AML_READ_WRITE));
- aml_append(crs,
- aml_interrupt(AML_CONSUMER, AML_LEVEL, AML_ACTIVE_HIGH,
- AML_EXCLUSIVE, &rtc_irq, 1));
- aml_append(dev, aml_name_decl("_CRS", crs));
- aml_append(scope, dev);
-}
-
static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap)
{
Aml *dev, *crs;
@@ -571,12 +554,15 @@ build_dsdt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
/* Reserve space for header */
acpi_data_push(dsdt->buf, sizeof(AcpiTableHeader));
+ /* When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
+ * While UEFI can use libfdt to disable the RTC device node in the DTB that
+ * it passes to the OS, it cannot modify AML. Therefore, we won't generate
+ * the RTC ACPI device at all when using UEFI.
+ */
scope = aml_scope("\\_SB");
acpi_dsdt_add_cpus(scope, guest_info->smp_cpus);
acpi_dsdt_add_uart(scope, &memmap[VIRT_UART],
(irqmap[VIRT_UART] + ARM_SPI_BASE));
- acpi_dsdt_add_rtc(scope, &memmap[VIRT_RTC],
- (irqmap[VIRT_RTC] + ARM_SPI_BASE));
acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]);
acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO],
(irqmap[VIRT_MMIO] + ARM_SPI_BASE), NUM_VIRTIO_TRANSPORTS);
--
2.1.0
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI
2016-01-15 14:11 [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI Shannon Zhao
@ 2016-01-15 14:18 ` Andrew Jones
2016-01-15 14:53 ` Peter Maydell
1 sibling, 0 replies; 3+ messages in thread
From: Andrew Jones @ 2016-01-15 14:18 UTC (permalink / raw)
To: Shannon Zhao
Cc: peter.maydell, ard.biesheuvel, edk2-devel, qemu-devel, qemu-arm,
zhaoshenglong, lersek
On Fri, Jan 15, 2016 at 10:11:31PM +0800, Shannon Zhao wrote:
> When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
> While UEFI can use libfdt to disable the RTC device node in the DTB that
> it passes to the OS, it cannot modify AML. Therefore, we won't generate
> the RTC ACPI device at all when using UEFI.
>
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> ---
> V3: add comments to explain why it doesn't generate RTC ACPI device
> ---
> hw/arm/virt-acpi-build.c | 24 +++++-------------------
> 1 file changed, 5 insertions(+), 19 deletions(-)
>
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 0caf5ce..0d5c635 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -94,23 +94,6 @@ static void acpi_dsdt_add_uart(Aml *scope, const MemMapEntry *uart_memmap,
> aml_append(scope, dev);
> }
>
> -static void acpi_dsdt_add_rtc(Aml *scope, const MemMapEntry *rtc_memmap,
> - uint32_t rtc_irq)
> -{
> - Aml *dev = aml_device("RTC0");
> - aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0013")));
> - aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> -
> - Aml *crs = aml_resource_template();
> - aml_append(crs, aml_memory32_fixed(rtc_memmap->base,
> - rtc_memmap->size, AML_READ_WRITE));
> - aml_append(crs,
> - aml_interrupt(AML_CONSUMER, AML_LEVEL, AML_ACTIVE_HIGH,
> - AML_EXCLUSIVE, &rtc_irq, 1));
> - aml_append(dev, aml_name_decl("_CRS", crs));
> - aml_append(scope, dev);
> -}
> -
> static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap)
> {
> Aml *dev, *crs;
> @@ -571,12 +554,15 @@ build_dsdt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
> /* Reserve space for header */
> acpi_data_push(dsdt->buf, sizeof(AcpiTableHeader));
>
> + /* When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
> + * While UEFI can use libfdt to disable the RTC device node in the DTB that
> + * it passes to the OS, it cannot modify AML. Therefore, we won't generate
> + * the RTC ACPI device at all when using UEFI.
> + */
> scope = aml_scope("\\_SB");
> acpi_dsdt_add_cpus(scope, guest_info->smp_cpus);
> acpi_dsdt_add_uart(scope, &memmap[VIRT_UART],
> (irqmap[VIRT_UART] + ARM_SPI_BASE));
> - acpi_dsdt_add_rtc(scope, &memmap[VIRT_RTC],
> - (irqmap[VIRT_RTC] + ARM_SPI_BASE));
> acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]);
> acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO],
> (irqmap[VIRT_MMIO] + ARM_SPI_BASE), NUM_VIRTIO_TRANSPORTS);
> --
> 2.1.0
>
>
Reviewed-by: Andrew Jones <drjones@redhat.com>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI
2016-01-15 14:11 [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI Shannon Zhao
2016-01-15 14:18 ` Andrew Jones
@ 2016-01-15 14:53 ` Peter Maydell
1 sibling, 0 replies; 3+ messages in thread
From: Peter Maydell @ 2016-01-15 14:53 UTC (permalink / raw)
To: Shannon Zhao
Cc: Ard Biesheuvel, edk2-devel@lists.01.org, QEMU Developers,
qemu-arm, Shannon Zhao, Laszlo Ersek
On 15 January 2016 at 14:11, Shannon Zhao <shannon.zhao@linaro.org> wrote:
> When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
> While UEFI can use libfdt to disable the RTC device node in the DTB that
> it passes to the OS, it cannot modify AML. Therefore, we won't generate
> the RTC ACPI device at all when using UEFI.
>
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> ---
> V3: add comments to explain why it doesn't generate RTC ACPI device
Applied to target-arm.next, thanks.
-- PMM
^ permalink raw reply [flat|nested] 3+ messages in thread
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2016-01-15 14:11 [Qemu-devel] [PATCH v3] ARM: Virt: Don't generate RTC ACPI device when using UEFI Shannon Zhao
2016-01-15 14:18 ` Andrew Jones
2016-01-15 14:53 ` Peter Maydell
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