diff options
Diffstat (limited to 'target/linux/ipq40xx/patches-4.14/865-ARM-dts-ipq4019-Add-TZ-and-SMEM-reserved-regions.patch')
| -rw-r--r-- | target/linux/ipq40xx/patches-4.14/865-ARM-dts-ipq4019-Add-TZ-and-SMEM-reserved-regions.patch | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/target/linux/ipq40xx/patches-4.14/865-ARM-dts-ipq4019-Add-TZ-and-SMEM-reserved-regions.patch b/target/linux/ipq40xx/patches-4.14/865-ARM-dts-ipq4019-Add-TZ-and-SMEM-reserved-regions.patch new file mode 100644 index 0000000000..56ae66b089 --- /dev/null +++ b/target/linux/ipq40xx/patches-4.14/865-ARM-dts-ipq4019-Add-TZ-and-SMEM-reserved-regions.patch @@ -0,0 +1,88 @@ +From fc566294610fa49e9d8c31c4ecc9c82f49b11f59 Mon Sep 17 00:00:00 2001 +From: Sven Eckelmann <sven.eckelmann@openmesh.com> +Date: Wed, 18 Apr 2018 09:10:44 +0200 +Subject: [PATCH] ARM: dts: ipq4019: Add TZ and SMEM reserved regions + +The QSEE (trustzone) is started on IPQ4019 before Linux is started. +According to QCA, it is placed in in the the memory region +0x87e80000-0x88000000 and must not be accessed directly. There is an +additional memory region 0x87e00000-0x87E80000 smem which which can be used +for communication with the TZ. The driver for the latter is not yet ready +but it is still not allowed to use this memory region like any other +memory region. + +Not reserving this memory region either leads to kernel crashes, kernel +hangs (often during the boot) or bus errors for userspace programs. The +latter happens when a program is using a memory region which is mapped to +these physical memory regions. + + [ 571.758058] Unhandled fault: imprecise external abort (0xc06) at 0x01715ff8 + [ 571.758099] pgd = cebec000 + [ 571.763826] [01715ff8] *pgd=8e7fa835, *pte=87e7f75f, *ppte=87e7fc7f + Bus error + +Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com> + +Forwarded: https://patchwork.kernel.org/patch/10347459/ +--- +Cc: Sricharan Ramabadhran <srichara@qti.qualcomm.com> +Cc: Senthilkumar N L <snlakshm@qti.qualcomm.com> + +There are additional memory regions which have to be initialized first by +Linux. So they are currently not used. We were told by QCA that the +features QSDK uses them for are: + +* crash dump feature + - a couple of regions used when 'qca,scm_restart_reason' dt node has the + value 'dload_status' not set to 1 + + apps_bl <0x87000000 0x400000> + + sbl <0x87400000 0x100000> + + cnss_debug <0x87400000 0x100000> + + cpu_context_dump <0x87b00000 0x080000> + - required driver not available in Linux + - safe to remove +* QSEE app execution + - region tz_apps <0x87b80000 0x280000> + - required driver not available in Linux + - safe to remove +* communication with TZ/QSEE + - region smem <0x87b80000 0x280000> + - driver changes not yet upstreamed + - must not be removed because any access can crash kernel/program +* trustzone (QSEE) private memory + - region tz <0x87e80000 0x180000> + - must not be removed because any access can crash kernel/program + +The problem with the missing regions was reported in 2016 [1]. So maybe +this change qualifies for a stable@vger.kernel.org submission. + +[1] https://www.spinics.net/lists/linux-arm-msm/msg21536.html +--- + arch/arm/boot/dts/qcom-ipq4019.dtsi | 16 ++++++++++++++++ + 1 file changed, 16 insertions(+) + +--- a/arch/arm/boot/dts/qcom-ipq4019.dtsi ++++ b/arch/arm/boot/dts/qcom-ipq4019.dtsi +@@ -23,6 +23,22 @@ + compatible = "qcom,ipq4019"; + interrupt-parent = <&intc>; + ++ reserved-memory { ++ #address-cells = <0x1>; ++ #size-cells = <0x1>; ++ ranges; ++ ++ smem_region: smem@87e00000 { ++ reg = <0x87e00000 0x080000>; ++ no-map; ++ }; ++ ++ tz@87e80000 { ++ reg = <0x87e80000 0x180000>; ++ no-map; ++ }; ++ }; ++ + aliases { + spi0 = &spi_0; + spi1 = &spi_1; |