Re: [PATCH] irqchip/gicv3-its: Add workaround for QDF2400 ITS erratum 0065
From: Shanker Donthineni
Date: Tue Mar 07 2017 - 09:24:26 EST
Hi Marc,
On 03/07/2017 02:03 AM, Marc Zyngier wrote:
On Sun, Mar 05 2017 at 3:23:56 pm GMT, Shanker Donthineni <shankerd@xxxxxxxxxxxxxx> wrote:
On Qualcomm Datacenter Technologies QDF2400 SoCs, the ITS hardware
implementation uses 16Bytes for Interrupt Translation Entry (ITTE),
nit: Interrupt Translation Entry is abbreviated as ITE. I know the vITS
has the ITTE thing all over the place, which I plan to address. No need
to respin for that.
Yeah, I saw your your patch in GICv4 branch which has change, I posted
v2 with your suggestion.
but reports an incorrect value of 8Bytes in GITS_TYPER.ITTE_size.
It might cause kernel memory corruption depending on the number
of MSI(x) that are configured and the amount of memory that has
been allocated for ITTEs in its_create_device().
This patch fixes the potential memory corruption by setting the
correct ITTE size to 16Bytes.
Signed-off-by: Shanker Donthineni <shankerd@xxxxxxxxxxxxxx>
---
Documentation/arm64/silicon-errata.txt | 1 +
arch/arm64/Kconfig | 10 ++++++++++
drivers/irqchip/irq-gic-v3-its.c | 16 ++++++++++++++++
3 files changed, 27 insertions(+)
diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
index a71b809..2f66683 100644
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -68,3 +68,4 @@ stable kernels.
| | | | |
| Qualcomm Tech. | Falkor v1 | E1003 | QCOM_FALKOR_ERRATUM_1003 |
| Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 |
+| Qualcomm Tech. | QDF2400 ITS | E0065 | QCOM_QDF2400_ERRATUM_0065 |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 896eba6..6bd51fb 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -509,6 +509,16 @@ config QCOM_FALKOR_ERRATUM_1009
If unsure, say Y.
+config QCOM_QDF2400_ERRATUM_0065
+ bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
+ default y
+ help
+ On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
+ ITTE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
+ been indicated as 16Bytes (0xf), not 8Bytes (0x7).
+
+ If unsure, say Y.
+
endmenu
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 2320100..86bd428 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1601,6 +1601,14 @@ static void __maybe_unused its_enable_quirk_cavium_23144(void *data)
its->flags |= ITS_FLAGS_WORKAROUND_CAVIUM_23144;
}
+static void __maybe_unused its_enable_quirk_qdf2400_e0065(void *data)
+{
+ struct its_node *its = data;
+
+ /* On QDF2400, the size of the ITTE is 16Bytes */
+ its->ite_size = 16;
+}
+
static const struct gic_quirk its_quirks[] = {
#ifdef CONFIG_CAVIUM_ERRATUM_22375
{
@@ -1618,6 +1626,14 @@ static void __maybe_unused its_enable_quirk_cavium_23144(void *data)
.init = its_enable_quirk_cavium_23144,
},
#endif
+#ifdef CONFIG_QCOM_QDF2400_ERRATUM_0065
+ {
+ .desc = "ITS: QDF2400 erratum 0065",
+ .iidr = 0x00001070, /* QDF2400 ITS rev 1.x */
+ .mask = 0xffffffff,
+ .init = its_enable_quirk_qdf2400_e0065,
+ },
+#endif
{
}
};
OK, that's pretty bad. Should this be CC stable?
Yes, please do CC stable if there is no merge conflicts.
Thanks,
M.
--
Shanker Donthineni
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.