| Message ID | 1378351680-14696-2-git-send-email-acourbot@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/04/2013 10:27 PM, Alexandre Courbot wrote: > Trusted Foundations is a TrustZone-based secure monitor for ARM that > can be invoked using a consistent SMC-based API on all supported > platforms. This patch adds initial basic support for Trusted > Foundations using the ARM firmware API. Current features are limited > to the ability to boot secondary processors. > > Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> > Reviewed-by: Tomasz Figa <t.figa@samsung.com> > Reviewed-by: Stephen Warren <swarren@nvidia.com> > --- > .../arm/firmware/tl,trusted-foundations.txt | 17 +++++ > .../devicetree/bindings/vendor-prefixes.txt | 1 + > arch/arm/Kconfig | 2 + > arch/arm/Makefile | 1 + > arch/arm/firmware/Kconfig | 25 +++++++ > arch/arm/firmware/Makefile | 1 + > arch/arm/firmware/trusted_foundations.c | 82 ++++++++++++++++++++++ > arch/arm/include/asm/trusted_foundations.h | 53 ++++++++++++++ > 8 files changed, 182 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt > create mode 100644 arch/arm/firmware/Kconfig > create mode 100644 arch/arm/firmware/Makefile > create mode 100644 arch/arm/firmware/trusted_foundations.c > create mode 100644 arch/arm/include/asm/trusted_foundations.h > > diff --git a/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt > new file mode 100644 > index 0000000..3954bbd > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt > @@ -0,0 +1,17 @@ > +Trusted Foundations > + > +Boards that use the Trusted Foundations secure monitor can signal its > +presence by declaring a node compatible with "tl,trusted-foundations" > +under the root node. > + > +Required properties: > +- compatible : "tl,trusted-foundations" > +- version-major : major version number of Trusted Foundations firmware > +- version-minor: minor version number of Trusted Foundations firmware > + > +Example: > + firmware { > + compatible = "tl,trusted-foundations"; > + version-major = <2>; > + version-minor = <8>; > + }; I'm wondering how we fit this in with PSCI bindings? Both are pieces of firmware functionality and may co-exist. There's nothing incompatible here, but there should be some commonality. Will future versions of Trusted Foundations follow the SMC calling conventions doc? What about armv8 support. Rob > diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt > index 366ce9b..20d61f3 100644 > --- a/Documentation/devicetree/bindings/vendor-prefixes.txt > +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt > @@ -63,6 +63,7 @@ ste ST-Ericsson > stericsson ST-Ericsson > toumaz Toumaz > ti Texas Instruments > +tl Trusted Logic > toshiba Toshiba Corporation > v3 V3 Semiconductor > via VIA Technologies, Inc. > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 43594d5..7fbe800 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -1074,6 +1074,8 @@ config ARM_TIMER_SP804 > select CLKSRC_MMIO > select CLKSRC_OF if OF > > +source "arch/arm/firmware/Kconfig" > + > source arch/arm/mm/Kconfig > > config ARM_NR_BANKS > diff --git a/arch/arm/Makefile b/arch/arm/Makefile > index 6fd2cea..a48de17 100644 > --- a/arch/arm/Makefile > +++ b/arch/arm/Makefile > @@ -267,6 +267,7 @@ core-$(CONFIG_KVM_ARM_HOST) += arch/arm/kvm/ > core-y += arch/arm/kernel/ arch/arm/mm/ arch/arm/common/ > core-y += arch/arm/net/ > core-y += arch/arm/crypto/ > +core-y += arch/arm/firmware/ > core-y += $(machdirs) $(platdirs) > > drivers-$(CONFIG_OPROFILE) += arch/arm/oprofile/ > diff --git a/arch/arm/firmware/Kconfig b/arch/arm/firmware/Kconfig > new file mode 100644 > index 0000000..ccf44c8 > --- /dev/null > +++ b/arch/arm/firmware/Kconfig > @@ -0,0 +1,25 @@ > +config ARCH_SUPPORTS_FIRMWARE > + bool > + > +config ARCH_SUPPORTS_TRUSTED_FOUNDATIONS > + bool > + select ARCH_SUPPORTS_FIRMWARE > + > +menu "Firmware options" > + depends on ARCH_SUPPORTS_FIRMWARE > + > +config TRUSTED_FOUNDATIONS > + bool "Trusted Foundations secure monitor support" > + depends on ARCH_SUPPORTS_TRUSTED_FOUNDATIONS > + help > + Some devices are booted with the Trusted Foundations secure monitor > + active, requiring some core operations to be performed by the secure > + monitor instead of the kernel. > + > + This option allows the kernel to invoke the secure monitor whenever > + required on devices using Trusted Foundations. See > + arch/arm/include/asm/trusted_foundations.h or the > + tl,trusted-foundations device tree binding documentation for details > + on how to use it. > + > +endmenu > diff --git a/arch/arm/firmware/Makefile b/arch/arm/firmware/Makefile > new file mode 100644 > index 0000000..a71f165 > --- /dev/null > +++ b/arch/arm/firmware/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_TRUSTED_FOUNDATIONS) += trusted_foundations.o > diff --git a/arch/arm/firmware/trusted_foundations.c b/arch/arm/firmware/trusted_foundations.c > new file mode 100644 > index 0000000..210ef83 > --- /dev/null > +++ b/arch/arm/firmware/trusted_foundations.c > @@ -0,0 +1,82 @@ > +/* > + * Trusted Foundations support for ARM CPUs > + * > + * Copyright (c) 2013, NVIDIA Corporation. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that 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. > + */ > + > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/of.h> > +#include <asm/firmware.h> > +#include <asm/trusted_foundations.h> > + > +#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200 > + > +static void __naked tf_generic_smc(u32 type, u32 subtype, u32 arg) > +{ > + asm volatile( > + ".arch_extension sec\n\t" > + "stmfd sp!, {r4 - r11, lr}\n\t" > + __asmeq("%0", "r0") > + __asmeq("%1", "r1") > + __asmeq("%2", "r2") > + "mov r3, #0\n\t" > + "mov r4, #0\n\t" > + "smc #0\n\t" > + "ldmfd sp!, {r4 - r11, pc}" > + : > + : "r" (type), "r" (subtype), "r" (arg) > + : "memory"); > +} > + > +static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr) > +{ > + tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, boot_addr, 0); > + > + return 0; > +} > + > +static const struct firmware_ops trusted_foundations_ops = { > + .set_cpu_boot_addr = tf_set_cpu_boot_addr, > +}; > + > +void register_trusted_foundations(struct trusted_foundations_platform_data *pd) > +{ > + /* we are not using version information for now since currently > + * supported SMCs are compatible with all TF releases */ > + register_firmware_ops(&trusted_foundations_ops); > +} > + > +#if IS_ENABLED(CONFIG_OF) > + > +void of_register_trusted_foundations(void) > +{ > + struct device_node *node; > + struct trusted_foundations_platform_data pdata; > + int err; > + > + node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"); > + > + if (!node) > + return; > + > + err = of_property_read_u32(node, "version-major", &pdata.version_major); > + if (err != 0) > + panic("Trusted Foundation: missing version-major property\n"); > + err = of_property_read_u32(node, "version-minor", &pdata.version_minor); > + if (err != 0) > + panic("Trusted Foundation: missing version-minor property\n"); > + register_trusted_foundations(&pdata); > +} > + > +#endif /* CONFIG_OF */ > diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h > new file mode 100644 > index 0000000..558f616 > --- /dev/null > +++ b/arch/arm/include/asm/trusted_foundations.h > @@ -0,0 +1,53 @@ > +/* > + * Copyright (c) 2013, NVIDIA Corporation. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that 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. > + */ > + > +#ifndef __ASM_ARM_TRUSTED_FOUNDATIONS_H > +#define __ASM_ARM_TRUSTED_FOUNDATIONS_H > + > +#include <linux/kconfig.h> > + > +struct trusted_foundations_platform_data { > + unsigned int version_major; > + unsigned int version_minor; > +}; > + > +#if IS_ENABLED(CONFIG_TRUSTED_FOUNDATIONS) > +void register_trusted_foundations(struct trusted_foundations_platform_data *pd); > +#if IS_ENABLED(CONFIG_OF) > +void of_register_trusted_foundations(void); > +#endif > + > +#else /* CONFIG_TRUSTED_FOUNDATIONS */ > + > +#include <linux/printk.h> > +#include <linux/of.h> > +#include <asm/bug.h> > + > +static inline void register_trusted_foundations( > + struct trusted_foundations_platform_data *pd) > +{ > + panic("No support for Trusted Foundations, stopping...\n"); > +} > + > +#if IS_ENABLED(CONFIG_OF) > +static inline void of_register_trusted_foundations(void) > +{ > + if (of_find_compatible_node(NULL, NULL, "tl,trusted-foundations")) > + register_trusted_foundations(NULL); > +} > +#endif > + > +#endif /* CONFIG_TRUSTED_FOUNDATIONS */ > + > +#endif >
On Thu, Sep 5, 2013 at 5:27 AM, Alexandre Courbot <acourbot@nvidia.com> wrote: > Trusted Foundations is a TrustZone-based secure monitor for ARM that > can be invoked using a consistent SMC-based API on all supported > platforms. This patch adds initial basic support for Trusted > Foundations using the ARM firmware API. Current features are limited > to the ability to boot secondary processors. > > Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> > Reviewed-by: Tomasz Figa <t.figa@samsung.com> > Reviewed-by: Stephen Warren <swarren@nvidia.com> I take it that this means that it is a set of standard routines living in the secure world that can be called by way of this API, correct? The commit message is written a bit like everybody knows what this is about but I don't :-) Some more background here would be nice, like where did this thing come from, and are there other platforms in existance that use trusted foundations or is it a Tegra-only thing? Does a specification of this thing listing available services exist for example? How does it relate to the (arch-neutral) trusted execution environment and such things that other vendors are pushing for? Can the trusted foundations be used "underneath" such frameworks for trusted applications, or is it a parallell thing altogether? Simple things like that... I tried googling it, is this a relevant URL? http://www.arm.com/community/partners/display_product/rw/ProductId/5393/ Thanks, Linus Walleij
On 09/04/2013 09:27 PM, Alexandre Courbot wrote: > Trusted Foundations is a TrustZone-based secure monitor for ARM that > can be invoked using a consistent SMC-based API on all supported > platforms. This patch adds initial basic support for Trusted > Foundations using the ARM firmware API. Current features are limited > to the ability to boot secondary processors. > diff --git a/arch/arm/firmware/trusted_foundations.c b/arch/arm/firmware/trusted_foundations.c ... > +void of_register_trusted_foundations(void) > +{ > + struct device_node *node; > + struct trusted_foundations_platform_data pdata; > + int err; > + > + node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"); > + > + if (!node) > + return; If you're going to revise this patch for the comment below, then I would suggest removing the blank line before that if statement. > diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h Do we need to add the following here: #if !IS_ENABLED(CONFIG_OF) static inline void register_trusted_foundations(...) {} #endif So that there is a dummy no-op function for the non-DT-support case? I guess Tegra always has CONFIG_OF enabled so that call from mach-tegra/common.c in patch 2 will never be an issue, but perhaps it might if anyone else uses this?
On Fri, Sep 6, 2013 at 3:35 AM, Rob Herring <robherring2@gmail.com> wrote: > On 09/04/2013 10:27 PM, Alexandre Courbot wrote: >> Trusted Foundations is a TrustZone-based secure monitor for ARM that >> can be invoked using a consistent SMC-based API on all supported >> platforms. This patch adds initial basic support for Trusted >> Foundations using the ARM firmware API. Current features are limited >> to the ability to boot secondary processors. >> >> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> >> Reviewed-by: Tomasz Figa <t.figa@samsung.com> >> Reviewed-by: Stephen Warren <swarren@nvidia.com> >> --- >> .../arm/firmware/tl,trusted-foundations.txt | 17 +++++ >> .../devicetree/bindings/vendor-prefixes.txt | 1 + >> arch/arm/Kconfig | 2 + >> arch/arm/Makefile | 1 + >> arch/arm/firmware/Kconfig | 25 +++++++ >> arch/arm/firmware/Makefile | 1 + >> arch/arm/firmware/trusted_foundations.c | 82 ++++++++++++++++++++++ >> arch/arm/include/asm/trusted_foundations.h | 53 ++++++++++++++ >> 8 files changed, 182 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >> create mode 100644 arch/arm/firmware/Kconfig >> create mode 100644 arch/arm/firmware/Makefile >> create mode 100644 arch/arm/firmware/trusted_foundations.c >> create mode 100644 arch/arm/include/asm/trusted_foundations.h >> >> diff --git a/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >> new file mode 100644 >> index 0000000..3954bbd >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >> @@ -0,0 +1,17 @@ >> +Trusted Foundations >> + >> +Boards that use the Trusted Foundations secure monitor can signal its >> +presence by declaring a node compatible with "tl,trusted-foundations" >> +under the root node. >> + >> +Required properties: >> +- compatible : "tl,trusted-foundations" >> +- version-major : major version number of Trusted Foundations firmware >> +- version-minor: minor version number of Trusted Foundations firmware >> + >> +Example: >> + firmware { >> + compatible = "tl,trusted-foundations"; >> + version-major = <2>; >> + version-minor = <8>; >> + }; > > I'm wondering how we fit this in with PSCI bindings? Both are pieces of > firmware functionality and may co-exist. There's nothing incompatible > here, but there should be some commonality. Will future versions of > Trusted Foundations follow the SMC calling conventions doc? What about > armv8 support. I don't have any information about the future of TF unfortunately, excepted that it should remain backward-compatible. What is this SMC calling convention doc your are talking about btw? Is there a standard calling convention defined by ARM? Alex.
On Sat, Sep 7, 2013 at 1:48 AM, Linus Walleij <linus.walleij@linaro.org> wrote: > On Thu, Sep 5, 2013 at 5:27 AM, Alexandre Courbot <acourbot@nvidia.com> wrote: > >> Trusted Foundations is a TrustZone-based secure monitor for ARM that >> can be invoked using a consistent SMC-based API on all supported >> platforms. This patch adds initial basic support for Trusted >> Foundations using the ARM firmware API. Current features are limited >> to the ability to boot secondary processors. >> >> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> >> Reviewed-by: Tomasz Figa <t.figa@samsung.com> >> Reviewed-by: Stephen Warren <swarren@nvidia.com> > > I take it that this means that it is a set of standard routines > living in the secure world that can be called by way of this > API, correct? The commit message is written a bit like > everybody knows what this is about but I don't :-) It's actually written a bit like I don't really know what this is about, thanks for exposing my ignorance. :P > Some more background here would be nice, like where did this > thing come from, and are there other platforms in existance that > use trusted foundations or is it a Tegra-only thing? Does a > specification of this thing listing available services exist for > example? There is unfortunately no public specification of this AFAIK. Client (kernel) side sources are available as Tegra downstream kernel releases, but that's about it. > How does it relate to the (arch-neutral) trusted execution > environment and such things that other vendors are pushing for? > Can the trusted foundations be used "underneath" such > frameworks for trusted applications, or is it a parallell thing > altogether? My understanding is that TF serves the same purpose for ARM only AFAICT. > I tried googling it, is this a relevant URL? > http://www.arm.com/community/partners/display_product/rw/ProductId/5393/ Yes. TF is an essential feature to support in order to boot the kernel on some Tegra-based consumer devices (e.g. SHIELD). Basic things such as secondary CPU control must be performed through SMCs. It has many more features but for the moment I don't see a need to go beyond the very basic. The issue is that as you pointed out, public information is scarce and future direction uncertain. That's why this patchset limits itself to what is needed to get secondary CPUs running - the procedure is very simple and unlikely to change in the future. DT binding is also as concise as possible to allow malleability since we cannot predict how it will evolve in the future. I will try to explain better what TF is in the commit log - at least as far as I understand it myself. Alex.
On Sat, Sep 7, 2013 at 4:29 AM, Stephen Warren <swarren@wwwdotorg.org> wrote: > On 09/04/2013 09:27 PM, Alexandre Courbot wrote: >> Trusted Foundations is a TrustZone-based secure monitor for ARM that >> can be invoked using a consistent SMC-based API on all supported >> platforms. This patch adds initial basic support for Trusted >> Foundations using the ARM firmware API. Current features are limited >> to the ability to boot secondary processors. > >> diff --git a/arch/arm/firmware/trusted_foundations.c b/arch/arm/firmware/trusted_foundations.c > ... >> +void of_register_trusted_foundations(void) >> +{ >> + struct device_node *node; >> + struct trusted_foundations_platform_data pdata; >> + int err; >> + >> + node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"); >> + >> + if (!node) >> + return; > > If you're going to revise this patch for the comment below, then I would > suggest removing the blank line before that if statement. Sure. > >> diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h > > Do we need to add the following here: > > #if !IS_ENABLED(CONFIG_OF) > static inline void register_trusted_foundations(...) {} > #endif > > So that there is a dummy no-op function for the non-DT-support case? I > guess Tegra always has CONFIG_OF enabled so that call from > mach-tegra/common.c in patch 2 will never be an issue, but perhaps it > might if anyone else uses this? My expectation is that register_trusted_foundations() is called by the platform code once it has established (through whatever mean it likes) that Trusted Foundations is required. For platforms supporting DT, of_register_trusted_foundations() takes care of that. Platforms that don't support DT need another way to decide whether they *need* TF or not. Once a platform decided that it needs TF, its absence is not an option, and therefore I'd think that register_trusted_foundations() should hard-fail if support is not compiled in. Or maybe I missed your point? Alex.
On 09/09/2013 12:38 AM, Alexandre Courbot wrote: > On Sat, Sep 7, 2013 at 4:29 AM, Stephen Warren <swarren@wwwdotorg.org> wrote: >> On 09/04/2013 09:27 PM, Alexandre Courbot wrote: >>> Trusted Foundations is a TrustZone-based secure monitor for ARM that >>> can be invoked using a consistent SMC-based API on all supported >>> platforms. This patch adds initial basic support for Trusted >>> Foundations using the ARM firmware API. Current features are limited >>> to the ability to boot secondary processors. >>> diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h >> >> Do we need to add the following here: >> >> #if !IS_ENABLED(CONFIG_OF) >> static inline void register_trusted_foundations(...) {} >> #endif Uggh. I meant to write **of_**register_trusted_foundations() there. >> So that there is a dummy no-op function for the non-DT-support case? I >> guess Tegra always has CONFIG_OF enabled so that call from >> mach-tegra/common.c in patch 2 will never be an issue, but perhaps it >> might if anyone else uses this? > > My expectation is that register_trusted_foundations() is called by the > platform code once it has established (through whatever mean it likes) > that Trusted Foundations is required. For platforms supporting DT, > of_register_trusted_foundations() takes care of that. Platforms that > don't support DT need another way to decide whether they *need* TF or > not. Once a platform decided that it needs TF, its absence is not an > option, and therefore I'd think that register_trusted_foundations() > should hard-fail if support is not compiled in. Or maybe I missed your > point? So yes, you missed my point, but it was my fault:-) Most of_* can be called irrespective of CONFIG_OF, and since of_register_trusted_foundations() is meant to handle internally the "do I need to do anything" case, I think it makes sense to be allowed to call it unconditionally without determining anything about either CONFIG_OF or TF DT node presence?
Hi guys, On Mon, Sep 09, 2013 at 07:15:31AM +0100, Alexandre Courbot wrote: > On Fri, Sep 6, 2013 at 3:35 AM, Rob Herring <robherring2@gmail.com> wrote: > > On 09/04/2013 10:27 PM, Alexandre Courbot wrote: > >> Trusted Foundations is a TrustZone-based secure monitor for ARM that > >> can be invoked using a consistent SMC-based API on all supported > >> platforms. This patch adds initial basic support for Trusted > >> Foundations using the ARM firmware API. Current features are limited > >> to the ability to boot secondary processors. [...] > >> +Example: > >> + firmware { > >> + compatible = "tl,trusted-foundations"; > >> + version-major = <2>; > >> + version-minor = <8>; > >> + }; > > > > I'm wondering how we fit this in with PSCI bindings? Both are pieces of > > firmware functionality and may co-exist. There's nothing incompatible > > here, but there should be some commonality. Will future versions of > > Trusted Foundations follow the SMC calling conventions doc? What about > > armv8 support. > > I don't have any information about the future of TF unfortunately, > excepted that it should remain backward-compatible. What is this SMC > calling convention doc your are talking about btw? Is there a standard > calling convention defined by ARM? SMC calling convention: https://silver.arm.com/download/download.tm?pv=1435186 PSCI: https://silver.arm.com/download/download.tm?pv=1421585 Although access to these documents requires you to go through a click-through license. Will
On 9 September 2013 07:15, Alexandre Courbot <gnurou@gmail.com> wrote: > On Fri, Sep 6, 2013 at 3:35 AM, Rob Herring <robherring2@gmail.com> wrote: >> On 09/04/2013 10:27 PM, Alexandre Courbot wrote: >>> Trusted Foundations is a TrustZone-based secure monitor for ARM that >>> can be invoked using a consistent SMC-based API on all supported >>> platforms. This patch adds initial basic support for Trusted >>> Foundations using the ARM firmware API. Current features are limited >>> to the ability to boot secondary processors. >>> >>> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> >>> Reviewed-by: Tomasz Figa <t.figa@samsung.com> >>> Reviewed-by: Stephen Warren <swarren@nvidia.com> >>> --- >>> .../arm/firmware/tl,trusted-foundations.txt | 17 +++++ >>> .../devicetree/bindings/vendor-prefixes.txt | 1 + >>> arch/arm/Kconfig | 2 + >>> arch/arm/Makefile | 1 + >>> arch/arm/firmware/Kconfig | 25 +++++++ >>> arch/arm/firmware/Makefile | 1 + >>> arch/arm/firmware/trusted_foundations.c | 82 ++++++++++++++++++++++ >>> arch/arm/include/asm/trusted_foundations.h | 53 ++++++++++++++ >>> 8 files changed, 182 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >>> create mode 100644 arch/arm/firmware/Kconfig >>> create mode 100644 arch/arm/firmware/Makefile >>> create mode 100644 arch/arm/firmware/trusted_foundations.c >>> create mode 100644 arch/arm/include/asm/trusted_foundations.h >>> >>> diff --git a/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >>> new file mode 100644 >>> index 0000000..3954bbd >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt >>> @@ -0,0 +1,17 @@ >>> +Trusted Foundations >>> + >>> +Boards that use the Trusted Foundations secure monitor can signal its >>> +presence by declaring a node compatible with "tl,trusted-foundations" >>> +under the root node. >>> + >>> +Required properties: >>> +- compatible : "tl,trusted-foundations" >>> +- version-major : major version number of Trusted Foundations firmware >>> +- version-minor: minor version number of Trusted Foundations firmware >>> + >>> +Example: >>> + firmware { >>> + compatible = "tl,trusted-foundations"; >>> + version-major = <2>; >>> + version-minor = <8>; >>> + }; >> >> I'm wondering how we fit this in with PSCI bindings? Both are pieces of >> firmware functionality and may co-exist. There's nothing incompatible >> here, but there should be some commonality. Will future versions of >> Trusted Foundations follow the SMC calling conventions doc? What about >> armv8 support. > > I don't have any information about the future of TF unfortunately, > excepted that it should remain backward-compatible. What is this SMC > calling convention doc your are talking about btw? Is there a standard > calling convention defined by ARM? The SMC calling convention is here (it requires free registration): http://infocenter.arm.com/help/topic/com.arm.doc.den0028a/index.html From the introduction: "This document defines a common calling mechanism for use with the Secure Monitor Call (SMC) instruction in both the ARMv7 and ARMv8 architectures. The SMC instruction is used to generate a synchronous exception that is handled by Secure Monitor code running in EL3. The arguments are passed in registers and then used to select which Secure function to execute. These calls may then be passed on to a Trusted OS in S-EL1. This specification aims to ease integration and reduce fragmentation between software layers, such as Operating Systems, Hypervisors, Trusted OS, Secure Monitor and System Firmware." If you talk about booting secondary CPUs, there is also PSCI: http://infocenter.arm.com/help/topic/com.arm.doc.den0022b/index.html
On Tue, Sep 10, 2013 at 3:04 PM, Will Deacon <will.deacon@arm.com> wrote: > On Mon, Sep 09, 2013 at 07:15:31AM +0100, Alexandre Courbot wrote: >> I don't have any information about the future of TF unfortunately, >> excepted that it should remain backward-compatible. What is this SMC >> calling convention doc your are talking about btw? Is there a standard >> calling convention defined by ARM? > > SMC calling convention: > https://silver.arm.com/download/download.tm?pv=1435186 According to the SMC calling convention r0 should be the SMC function identifier. +static void __naked tf_generic_smc(u32 type, u32 subtype, u32 arg) +{ + asm volatile( + ".arch_extension sec\n\t" + "stmfd sp!, {r4 - r11, lr}\n\t" + __asmeq("%0", "r0") + __asmeq("%1", "r1") + __asmeq("%2", "r2") + "mov r3, #0\n\t" + "mov r4, #0\n\t" + "smc #0\n\t" + "ldmfd sp!, {r4 - r11, pc}" + : + : "r" (type), "r" (subtype), "r" (arg) + : "memory"); +} So type == function identifier? Or are these two totally different things, such that trusted foundations are already a different beast that what the SMC calling convention specifies? Anyway: r0,r1,r2 = type/subtype/arg. +#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200 (...) +static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr) +{ + tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, boot_addr, 0); + + return 0; +} What kind of a "subtype" is the boot address? I could have accepted it if the *last* thing, the argument contained the boot address. With the type/subtype/arg convention it would be more natural if the "subtype" was something like 0. Should the SMC function rather have this signature: tf_generic_smc(u32 type, u32 arg1, u32 arg2) ? Then *sometimes* arg1 is a subtype, if the "type" is such that it takes a subtype? (That's a rough guess.) So to begin with the arguments to tf_generic_smc() are either confusingly named or tf_set_cpu_boot_addr() begins the journey with violating the function signature. I also wonder what kind if "type" starts its enumerator on 0xfffff200? Wouldn't it be more natural if it was e.g. 1? It looks like the TF_SET_CPU_BOOT_ADDR_SMC reflects some bit-wise encoding scheme, so some details here wouldn't hurt? The main thing is that the patch has to say that this is an API toward trusted foundations, that it has nothing to do with the SMC calling conventions, and only pertain to devices that use trusted foundations, so as to avoid any confusion. Then I'm game :-) Yours, Linus Walleij
On Thu, Sep 12, 2013 at 6:18 PM, Linus Walleij <linus.walleij@linaro.org> wrote: > On Tue, Sep 10, 2013 at 3:04 PM, Will Deacon <will.deacon@arm.com> wrote: >> On Mon, Sep 09, 2013 at 07:15:31AM +0100, Alexandre Courbot wrote: > >>> I don't have any information about the future of TF unfortunately, >>> excepted that it should remain backward-compatible. What is this SMC >>> calling convention doc your are talking about btw? Is there a standard >>> calling convention defined by ARM? >> >> SMC calling convention: >> https://silver.arm.com/download/download.tm?pv=1435186 > > According to the SMC calling convention r0 should be > the SMC function identifier. > > +static void __naked tf_generic_smc(u32 type, u32 subtype, u32 arg) > +{ > + asm volatile( > + ".arch_extension sec\n\t" > + "stmfd sp!, {r4 - r11, lr}\n\t" > + __asmeq("%0", "r0") > + __asmeq("%1", "r1") > + __asmeq("%2", "r2") > + "mov r3, #0\n\t" > + "mov r4, #0\n\t" > + "smc #0\n\t" > + "ldmfd sp!, {r4 - r11, pc}" > + : > + : "r" (type), "r" (subtype), "r" (arg) > + : "memory"); > +} > > So type == function identifier? Or are these two totally > different things, such that trusted foundations are already > a different beast that what the SMC calling convention > specifies? After looking at the documents linked by Will and Catalin (thanks!), I can state with confidence that TF does not follow the SMC calling convention and has nothing to do with PSCI neither. The value passed in r0 does not match the function identifier definition at all: with its two MSBs set to 1, it would be interpreted as a SMC64 Fast Call, which it clearly is not. There is also no correspondance with any of the functions ids defined in the PSCI specification. > Anyway: > r0,r1,r2 = type/subtype/arg. > > +#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200 > (...) > +static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr) > +{ > + tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, boot_addr, 0); > + > + return 0; > +} > > What kind of a "subtype" is the boot address? I could have > accepted it if the *last* thing, the argument contained the boot > address. With the type/subtype/arg convention it would be > more natural if the "subtype" was something like 0. > > Should the SMC function rather have this signature: > > tf_generic_smc(u32 type, u32 arg1, u32 arg2) > > ? > > Then *sometimes* arg1 is a subtype, if the "type" is > such that it takes a subtype? > > (That's a rough guess.) > > So to begin with the arguments to tf_generic_smc() are either > confusingly named or tf_set_cpu_boot_addr() begins the > journey with violating the function signature. Indeed the subtype parameter is poorly named. That will teach me reproducing the behavior of our downstream kernel without thinking. :/ > I also wonder what kind if "type" starts its enumerator on > 0xfffff200? Wouldn't it be more natural if it was e.g. 1? > It looks like the TF_SET_CPU_BOOT_ADDR_SMC > reflects some bit-wise encoding scheme, so some details > here wouldn't hurt? I agree, unfortunately this raw value is all the details I myself have access to. /o\ > The main thing is that the patch has to say that this > is an API toward trusted foundations, that it has nothing > to do with the SMC calling conventions, and only pertain > to devices that use trusted foundations, so as to avoid > any confusion. Note that the patch never claimed to follow the SMC calling conventions. You guys assumed it should for some reason. ;) But clearly, it cannot hurt to state this unambiguously, so I will make sure to do that. Then I hope the lack of detail about the non-standard calling convention will not be an obstacle to its merging, as this enables a bunch of retail Tegra devices (e.g. SHIELD) to boot. Thanks, Alex.
On Tue, Sep 10, 2013 at 12:59 AM, Stephen Warren <swarren@wwwdotorg.org> wrote: > On 09/09/2013 12:38 AM, Alexandre Courbot wrote: >> On Sat, Sep 7, 2013 at 4:29 AM, Stephen Warren <swarren@wwwdotorg.org> wrote: >>> On 09/04/2013 09:27 PM, Alexandre Courbot wrote: >>>> Trusted Foundations is a TrustZone-based secure monitor for ARM that >>>> can be invoked using a consistent SMC-based API on all supported >>>> platforms. This patch adds initial basic support for Trusted >>>> Foundations using the ARM firmware API. Current features are limited >>>> to the ability to boot secondary processors. > >>>> diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h >>> >>> Do we need to add the following here: >>> >>> #if !IS_ENABLED(CONFIG_OF) >>> static inline void register_trusted_foundations(...) {} >>> #endif > > Uggh. I meant to write **of_**register_trusted_foundations() there. > >>> So that there is a dummy no-op function for the non-DT-support case? I >>> guess Tegra always has CONFIG_OF enabled so that call from >>> mach-tegra/common.c in patch 2 will never be an issue, but perhaps it >>> might if anyone else uses this? >> >> My expectation is that register_trusted_foundations() is called by the >> platform code once it has established (through whatever mean it likes) >> that Trusted Foundations is required. For platforms supporting DT, >> of_register_trusted_foundations() takes care of that. Platforms that >> don't support DT need another way to decide whether they *need* TF or >> not. Once a platform decided that it needs TF, its absence is not an >> option, and therefore I'd think that register_trusted_foundations() >> should hard-fail if support is not compiled in. Or maybe I missed your >> point? > > So yes, you missed my point, but it was my fault:-) > > Most of_* can be called irrespective of CONFIG_OF, and since > of_register_trusted_foundations() is meant to handle internally the "do > I need to do anything" case, I think it makes sense to be allowed to > call it unconditionally without determining anything about either > CONFIG_OF or TF DT node presence? Ah, ok, I follow you now. I wasn't sure what the convention was here, but yeah, I see nothing against making a no-op of_register_trusted_foundations() available when CONFIG_OF is not enabled. Thanks, Alex.
diff --git a/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt new file mode 100644 index 0000000..3954bbd --- /dev/null +++ b/Documentation/devicetree/bindings/arm/firmware/tl,trusted-foundations.txt @@ -0,0 +1,17 @@ +Trusted Foundations + +Boards that use the Trusted Foundations secure monitor can signal its +presence by declaring a node compatible with "tl,trusted-foundations" +under the root node. + +Required properties: +- compatible : "tl,trusted-foundations" +- version-major : major version number of Trusted Foundations firmware +- version-minor: minor version number of Trusted Foundations firmware + +Example: + firmware { + compatible = "tl,trusted-foundations"; + version-major = <2>; + version-minor = <8>; + }; diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index 366ce9b..20d61f3 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -63,6 +63,7 @@ ste ST-Ericsson stericsson ST-Ericsson toumaz Toumaz ti Texas Instruments +tl Trusted Logic toshiba Toshiba Corporation v3 V3 Semiconductor via VIA Technologies, Inc. diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 43594d5..7fbe800 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1074,6 +1074,8 @@ config ARM_TIMER_SP804 select CLKSRC_MMIO select CLKSRC_OF if OF +source "arch/arm/firmware/Kconfig" + source arch/arm/mm/Kconfig config ARM_NR_BANKS diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 6fd2cea..a48de17 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -267,6 +267,7 @@ core-$(CONFIG_KVM_ARM_HOST) += arch/arm/kvm/ core-y += arch/arm/kernel/ arch/arm/mm/ arch/arm/common/ core-y += arch/arm/net/ core-y += arch/arm/crypto/ +core-y += arch/arm/firmware/ core-y += $(machdirs) $(platdirs) drivers-$(CONFIG_OPROFILE) += arch/arm/oprofile/ diff --git a/arch/arm/firmware/Kconfig b/arch/arm/firmware/Kconfig new file mode 100644 index 0000000..ccf44c8 --- /dev/null +++ b/arch/arm/firmware/Kconfig @@ -0,0 +1,25 @@ +config ARCH_SUPPORTS_FIRMWARE + bool + +config ARCH_SUPPORTS_TRUSTED_FOUNDATIONS + bool + select ARCH_SUPPORTS_FIRMWARE + +menu "Firmware options" + depends on ARCH_SUPPORTS_FIRMWARE + +config TRUSTED_FOUNDATIONS + bool "Trusted Foundations secure monitor support" + depends on ARCH_SUPPORTS_TRUSTED_FOUNDATIONS + help + Some devices are booted with the Trusted Foundations secure monitor + active, requiring some core operations to be performed by the secure + monitor instead of the kernel. + + This option allows the kernel to invoke the secure monitor whenever + required on devices using Trusted Foundations. See + arch/arm/include/asm/trusted_foundations.h or the + tl,trusted-foundations device tree binding documentation for details + on how to use it. + +endmenu diff --git a/arch/arm/firmware/Makefile b/arch/arm/firmware/Makefile new file mode 100644 index 0000000..a71f165 --- /dev/null +++ b/arch/arm/firmware/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_TRUSTED_FOUNDATIONS) += trusted_foundations.o diff --git a/arch/arm/firmware/trusted_foundations.c b/arch/arm/firmware/trusted_foundations.c new file mode 100644 index 0000000..210ef83 --- /dev/null +++ b/arch/arm/firmware/trusted_foundations.c @@ -0,0 +1,82 @@ +/* + * Trusted Foundations support for ARM CPUs + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that 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. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/of.h> +#include <asm/firmware.h> +#include <asm/trusted_foundations.h> + +#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200 + +static void __naked tf_generic_smc(u32 type, u32 subtype, u32 arg) +{ + asm volatile( + ".arch_extension sec\n\t" + "stmfd sp!, {r4 - r11, lr}\n\t" + __asmeq("%0", "r0") + __asmeq("%1", "r1") + __asmeq("%2", "r2") + "mov r3, #0\n\t" + "mov r4, #0\n\t" + "smc #0\n\t" + "ldmfd sp!, {r4 - r11, pc}" + : + : "r" (type), "r" (subtype), "r" (arg) + : "memory"); +} + +static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr) +{ + tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, boot_addr, 0); + + return 0; +} + +static const struct firmware_ops trusted_foundations_ops = { + .set_cpu_boot_addr = tf_set_cpu_boot_addr, +}; + +void register_trusted_foundations(struct trusted_foundations_platform_data *pd) +{ + /* we are not using version information for now since currently + * supported SMCs are compatible with all TF releases */ + register_firmware_ops(&trusted_foundations_ops); +} + +#if IS_ENABLED(CONFIG_OF) + +void of_register_trusted_foundations(void) +{ + struct device_node *node; + struct trusted_foundations_platform_data pdata; + int err; + + node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"); + + if (!node) + return; + + err = of_property_read_u32(node, "version-major", &pdata.version_major); + if (err != 0) + panic("Trusted Foundation: missing version-major property\n"); + err = of_property_read_u32(node, "version-minor", &pdata.version_minor); + if (err != 0) + panic("Trusted Foundation: missing version-minor property\n"); + register_trusted_foundations(&pdata); +} + +#endif /* CONFIG_OF */ diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h new file mode 100644 index 0000000..558f616 --- /dev/null +++ b/arch/arm/include/asm/trusted_foundations.h @@ -0,0 +1,53 @@ +/* + * Copyright (c) 2013, NVIDIA Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that 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. + */ + +#ifndef __ASM_ARM_TRUSTED_FOUNDATIONS_H +#define __ASM_ARM_TRUSTED_FOUNDATIONS_H + +#include <linux/kconfig.h> + +struct trusted_foundations_platform_data { + unsigned int version_major; + unsigned int version_minor; +}; + +#if IS_ENABLED(CONFIG_TRUSTED_FOUNDATIONS) +void register_trusted_foundations(struct trusted_foundations_platform_data *pd); +#if IS_ENABLED(CONFIG_OF) +void of_register_trusted_foundations(void); +#endif + +#else /* CONFIG_TRUSTED_FOUNDATIONS */ + +#include <linux/printk.h> +#include <linux/of.h> +#include <asm/bug.h> + +static inline void register_trusted_foundations( + struct trusted_foundations_platform_data *pd) +{ + panic("No support for Trusted Foundations, stopping...\n"); +} + +#if IS_ENABLED(CONFIG_OF) +static inline void of_register_trusted_foundations(void) +{ + if (of_find_compatible_node(NULL, NULL, "tl,trusted-foundations")) + register_trusted_foundations(NULL); +} +#endif + +#endif /* CONFIG_TRUSTED_FOUNDATIONS */ + +#endif