[Qemu-devel] [PATCH 0/2] sdhci: Implement device reset

[Qemu-devel] [PATCH 0/2] sdhci: Implement device reset

[Peter Maydell]

This patchset implements the DeviceClass reset method for
the sdhci devices, so that on QEMU system reset they are
reset. (Mostly guests didn't notice this was missing I
think because they tend to do a commanded reset via the
device register as part of driver initialization.)

For the reset patch to work and not crash QEMU on startup,
we need to fix a missing NULL pointer check in sd.c's
sd_get_inserted() function.

These patchsets apply on top of Andrew's rpi quirk
patchset which is in target-arm.next.

Review/testing appreciated.


Peter Maydell (2):
  sd.c: Handle NULL block backend in sd_get_inserted()
  sdhci: Implement DeviceClass reset

 hw/sd/sd.c    |  2 +-
 hw/sd/sdhci.c | 21 +++++++++++++++++----
 2 files changed, 18 insertions(+), 5 deletions(-)

-- 
1.9.1

[Qemu-devel] [PATCH 1/2] sd.c: Handle NULL block backend in sd_get_inserted()

[Peter Maydell]

The sd.c SD card emulation code can be in a state where the
SDState BlockBackend pointer is NULL; this is treated as
"card not present". Add a missing check to sd_get_inserted()
so that we don't segfault in this situation.

(This could be provoked by the guest writing to the SDHCI
register to do a reset on a xilinx-zynq-a9 board; it will
also happen at startup when sdhci implements its DeviceClass
reset method.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/sd/sd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index edb6b32..00c320d 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -449,7 +449,7 @@ static void sd_reset(DeviceState *dev)
 
 static bool sd_get_inserted(SDState *sd)
 {
-    return blk_is_inserted(sd->blk);
+    return sd->blk && blk_is_inserted(sd->blk);
 }
 
 static bool sd_get_readonly(SDState *sd)
-- 
1.9.1

Re: [Qemu-devel] [PATCH 1/2] sd.c: Handle NULL block backend in sd_get_inserted()

[Alistair Francis]

On Fri, Feb 26, 2016 at 5:24 AM, Peter Maydell <peter.maydell@linaro.org> wrote:
> The sd.c SD card emulation code can be in a state where the
> SDState BlockBackend pointer is NULL; this is treated as
> "card not present". Add a missing check to sd_get_inserted()
> so that we don't segfault in this situation.
>
> (This could be provoked by the guest writing to the SDHCI
> register to do a reset on a xilinx-zynq-a9 board; it will
> also happen at startup when sdhci implements its DeviceClass
> reset method.)
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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

Thanks,

Alistair

> ---
>  hw/sd/sd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/sd/sd.c b/hw/sd/sd.c
> index edb6b32..00c320d 100644
> --- a/hw/sd/sd.c
> +++ b/hw/sd/sd.c
> @@ -449,7 +449,7 @@ static void sd_reset(DeviceState *dev)
>
>  static bool sd_get_inserted(SDState *sd)
>  {
> -    return blk_is_inserted(sd->blk);
> +    return sd->blk && blk_is_inserted(sd->blk);
>  }
>
>  static bool sd_get_readonly(SDState *sd)
> --
> 1.9.1
>
>

[Qemu-devel] [PATCH 2/2] sdhci: Implement DeviceClass reset

[Peter Maydell]

The sdhci device was missing a DeviceClass reset method;
implement it. Poweron reset looks the same as reset commanded
by the guest via the device registers, apart from modelling of
the rpi 'pending insert interrupt on powerup' quirk.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/sd/sdhci.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index e087c17..d28b587 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -207,6 +207,21 @@ static void sdhci_reset(SDHCIState *s)
     s->pending_insert_state = false;
 }
 
+static void sdhci_poweron_reset(DeviceState *dev)
+{
+    /* QOM (ie power-on) reset. This is identical to reset
+     * commanded via device register apart from handling of the
+     * 'pending insert on powerup' quirk.
+     */
+    SDHCIState *s = (SDHCIState *)dev;
+
+    sdhci_reset(s);
+
+    if (s->pending_insert_quirk) {
+        s->pending_insert_state = true;
+    }
+}
+
 static void sdhci_data_transfer(void *opaque);
 
 static void sdhci_send_command(SDHCIState *s)
@@ -1290,6 +1305,7 @@ static void sdhci_pci_class_init(ObjectClass *klass, void *data)
     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
     dc->vmsd = &sdhci_vmstate;
     dc->props = sdhci_pci_properties;
+    dc->reset = sdhci_poweron_reset;
 }
 
 static const TypeInfo sdhci_pci_info = {
@@ -1332,10 +1348,6 @@ static void sdhci_sysbus_realize(DeviceState *dev, Error ** errp)
     memory_region_init_io(&s->iomem, OBJECT(s), &sdhci_mmio_ops, s, "sdhci",
             SDHC_REGISTERS_MAP_SIZE);
     sysbus_init_mmio(sbd, &s->iomem);
-
-    if (s->pending_insert_quirk) {
-        s->pending_insert_state = true;
-    }
 }
 
 static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
@@ -1345,6 +1357,7 @@ static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
     dc->vmsd = &sdhci_vmstate;
     dc->props = sdhci_sysbus_properties;
     dc->realize = sdhci_sysbus_realize;
+    dc->reset = sdhci_poweron_reset;
 }
 
 static const TypeInfo sdhci_sysbus_info = {
-- 
1.9.1

Re: [Qemu-devel] [PATCH 2/2] sdhci: Implement DeviceClass reset

[Andrew Baumann]

> From: Peter Maydell [mailto:peter.maydell@linaro.org]
> Sent: Friday, 26 February 2016 5:24 AM
> 
> The sdhci device was missing a DeviceClass reset method;
> implement it. Poweron reset looks the same as reset commanded
> by the guest via the device registers, apart from modelling of
> the rpi 'pending insert interrupt on powerup' quirk.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  hw/sd/sdhci.c | 21 +++++++++++++++++----
>  1 file changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> index e087c17..d28b587 100644
> --- a/hw/sd/sdhci.c
> +++ b/hw/sd/sdhci.c
> @@ -207,6 +207,21 @@ static void sdhci_reset(SDHCIState *s)
>      s->pending_insert_state = false;
>  }
> 
> +static void sdhci_poweron_reset(DeviceState *dev)
> +{
> +    /* QOM (ie power-on) reset. This is identical to reset
> +     * commanded via device register apart from handling of the
> +     * 'pending insert on powerup' quirk.
> +     */
> +    SDHCIState *s = (SDHCIState *)dev;
> +
> +    sdhci_reset(s);
> +
> +    if (s->pending_insert_quirk) {
> +        s->pending_insert_state = true;
> +    }
> +}
> +
>  static void sdhci_data_transfer(void *opaque);
> 
>  static void sdhci_send_command(SDHCIState *s)
> @@ -1290,6 +1305,7 @@ static void sdhci_pci_class_init(ObjectClass *klass,
> void *data)
>      set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
>      dc->vmsd = &sdhci_vmstate;
>      dc->props = sdhci_pci_properties;
> +    dc->reset = sdhci_poweron_reset;
>  }
> 
>  static const TypeInfo sdhci_pci_info = {
> @@ -1332,10 +1348,6 @@ static void sdhci_sysbus_realize(DeviceState *dev,
> Error ** errp)
>      memory_region_init_io(&s->iomem, OBJECT(s), &sdhci_mmio_ops, s,
> "sdhci",
>              SDHC_REGISTERS_MAP_SIZE);
>      sysbus_init_mmio(sbd, &s->iomem);
> -
> -    if (s->pending_insert_quirk) {
> -        s->pending_insert_state = true;
> -    }
>  }
> 
>  static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
> @@ -1345,6 +1357,7 @@ static void sdhci_sysbus_class_init(ObjectClass
> *klass, void *data)
>      dc->vmsd = &sdhci_vmstate;
>      dc->props = sdhci_sysbus_properties;
>      dc->realize = sdhci_sysbus_realize;
> +    dc->reset = sdhci_poweron_reset;
>  }
> 
>  static const TypeInfo sdhci_sysbus_info = {

Not tested, but the handling of the Pi quirk looks good to me, and it's trivial.

Reviewed-by: Andrew Baumann <Andrew.Baumann@microsoft.com>

BTW, now that you've done this, we could unify sdhci_pci_properties and sdhci_sysbus_properties. Let me know if you'd like a patch for that.

Cheers,
Andrew