x86/platform/intel/quark: Fix incorrect kernel-doc comment syntax in files

The opening comment mark '/**' is used for highlighting the beginning of
kernel-doc comments.
There are certain files in arch/x86/platform/intel-quark, which follow this
syntax, but the content inside does not comply with kernel-doc.
Such lines were probably not meant for kernel-doc parsing, but are parsed
due to the presence of kernel-doc like comment syntax(i.e, '/**'), which
causes unexpected warnings from kernel-doc.

E.g., presence of kernel-doc like comment in the header lines for
arch/x86/platform/intel-quark/imr.c causes these warnings:
"warning: Function parameter or member 'fmt' not described in 'pr_fmt'"
"warning: expecting prototype for c(). Prototype was for pr_fmt() instead"

Similarly for arch/x86/platform/intel-quark/imr_selftest.c too.

Provide a simple fix by replacing these occurrences with general comment
format, i.e. '/*', to prevent kernel-doc from parsing it.

Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210330213022.28769-1-yashsri421@gmail.com

x86: Fix various typos in comments

Fix ~144 single-word typos in arch/x86/ code comments.

Doing this in a single commit should reduce the churn.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org

x86/platform: Convert to new CPU match macros

The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

Get rid the of the local macro wrappers for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131509.359448901@linutronix.de

x86/platform/intel/quark: Explicitly include linux/io.h for virt_to_phys()

Similarly to the previous patches by Sean Christopherson:

"Through a labyrinthian sequence of includes, usage of virt_to_phys() is
dependent on the include of asm/io.h in x86's asm/realmode.h, which is
included in x86's asm/acpi.h and thus by linux/acpi.h. Explicitly
include linux/io.h to break the dependency on realmode.h so that a
future patch can remove the realmode.h include from acpi.h without
breaking the build."

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Link: https://lkml.kernel.org/r/157475520975.21853.16355518818746065226.tip-bot2@tip-bot2
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86: platform: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <x86@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: Add SPDX license identifier for missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/platform/quark: Re-use DEFINE_SHOW_ATTRIBUTE() macro

...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.

While here, replace permissions by explicit octal value.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180214154317.52290-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/platform/intel/quark: Drop IMR lock bit support

Isolated Memory Regions support a lock bit. The lock bit in an IMR prevents
modification of the IMR until the core goes through a warm or cold reset.
The lock bit feature is not useful in the context of the kernel API and is
not really necessary since modification of IMRs is possible only from
ring-zero anyway. This patch drops support for IMR locks bits, it
simplifies the kernel API and removes an unnecessary and needlessly complex
feature.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andriy.shevchenko@linux.intel.com
Cc: boon.leong.ong@intel.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/1456190999-12685-3-git-send-email-pure.logic@nexus-software.ie
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/platform/intel/quark: Change the kernel's IMR lock bit to false

Currently when setting up an IMR around the kernel's .text section we lock
that IMR, preventing further modification. While superficially this appears
to be the right thing to do, in fact this doesn't account for a legitimate
change in the memory map such as when executing a new kernel via kexec.

In such a scenario a second kernel can have a different size and location
to it's predecessor and can view some of the memory occupied by it's
predecessor as legitimately usable DMA RAM. If this RAM were then
subsequently allocated to DMA agents within the system it could conceivably
trigger an IMR violation.

This patch fixes the this potential situation by keeping the kernel's .text
section IMR lock bit false by default.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boon.leong.ong@intel.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/1456190999-12685-2-git-send-email-pure.logic@nexus-software.ie
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/platform: Make platform/intel-quark/imr.c explicitly non-modular

The Kconfig currently controlling compilation of this code is:

drivers/platform/x86/Kconfig:config INTEL_IMR
drivers/platform/x86/Kconfig: bool "Intel Isolated Memory Region support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1455491396-30977-2-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/platform/quark: Print boundaries correctly

When we print values, such as @size, we have to understand that
it's derived from [begin .. end] as:

size = end - begin + 1

On the opposite the @end is derived from the rest as:

end = begin + size - 1

Correct the IMR code to print values correctly.

Note that @__end_rodata actually points to the next address
after the aligned .rodata section.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453320821-64328-1-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/platform/iosf_mbi: Remove duplicate definitions

The read and write opcodes are global for all units on SoC and even across
Intel SoCs. Remove duplication of corresponding constants. At the same time
convert all current users.

No functional change.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Boon Leong Ong <boon.leong.ong@intel.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

x86/intel/quark: Fix simple_return.cocci warnings

arch/x86/platform/intel-quark/imr.c:129:1-4: WARNING: end returns can be simpified

Simplify a trivial if-return sequence. Possibly combine with a preceding function call.

Generated by: scripts/coccinelle/misc/simple_return.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Andy Shevchenko <andy.schevchenko@gmail.com>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: kbuild-all@01.org
Link: http://lkml.kernel.org/r/20150219081432.GA21996@waimea
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/intel/quark: Fix ptr_ret.cocci warnings

arch/x86/platform/intel-quark/imr.c:280:1-3: WARNING: PTR_ERR_OR_ZERO can be used

Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Andy Shevchenko <andy.schevchenko@gmail.com>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: kbuild-all@01.org
Link: http://lkml.kernel.org/r/20150219081432.GA21983@waimea
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/intel/quark: Add Isolated Memory Regions for Quark X1000

Intel's Quark X1000 SoC contains a set of registers called
Isolated Memory Regions. IMRs are accessed over the IOSF mailbox
interface. IMRs are areas carved out of memory that define
read/write access rights to the various system agents within the
Quark system. For a given agent in the system it is possible to
specify if that agent may read or write an area of memory
defined by an IMR with a granularity of 1 KiB.

Quark_SecureBootPRM_330234_001.pdf section 4.5 details the
concept of IMRs quark-x1000-datasheet.pdf section 12.7.4 details
the implementation of IMRs in silicon.

eSRAM flush, CPU Snoop write-only, CPU SMM Mode, CPU non-SMM
mode, RMU and PCIe Virtual Channels (VC0 and VC1) can have
individual read/write access masks applied to them for a given
memory region in Quark X1000. This enables IMRs to treat each
memory transaction type listed above on an individual basis and
to filter appropriately based on the IMR access mask for the
memory region. Quark supports eight IMRs.

Since all of the DMA capable SoC components in the X1000 are
mapped to VC0 it is possible to define sections of memory as
invalid for DMA write operations originating from Ethernet, USB,
SD and any other DMA capable south-cluster component on VC0.
Similarly it is possible to mark kernel memory as non-SMM mode
read/write only or to mark BIOS runtime memory as SMM mode
accessible only depending on the particular memory footprint on
a given system.

On an IMR violation Quark SoC X1000 systems are configured to
reset the system, so ensuring that the IMR memory map is
consistent with the EFI provided memory map is critical to
ensure no IMR violations reset the system.

The API for accessing IMRs is based on MTRR code but doesn't
provide a /proc or /sys interface to manipulate IMRs. Defining
the size and extent of IMRs is exclusively the domain of
in-kernel code.

Quark firmware sets up a series of locked IMRs around pieces of
memory that firmware owns such as ACPI runtime data. During boot
a series of unlocked IMRs are placed around items in memory to
guarantee no DMA modification of those items can take place.
Grub also places an unlocked IMR around the kernel boot params
data structure and compressed kernel image. It is necessary for
the kernel to tear down all unlocked IMRs in order to ensure
that the kernel's view of memory passed via the EFI memory map
is consistent with the IMR memory map. Without tearing down all
unlocked IMRs on boot transitory IMRs such as those used to
protect the compressed kernel image will cause IMR violations and system reboots.

The IMR init code tears down all unlocked IMRs and sets a
protective IMR around the kernel .text and .rodata as one
contiguous block. This sanitizes the IMR memory map with respect
to the EFI memory map and protects the read-only portions of the
kernel from unwarranted DMA access.

Tested-by: Ong, Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Reviewed-by: Andy Shevchenko <andy.schevchenko@gmail.com>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Reviewed-by: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: andy.shevchenko@gmail.com
Cc: dvhart@infradead.org
Link: http://lkml.kernel.org/r/1422635379-12476-2-git-send-email-pure.logic@nexus-software.ie
Signed-off-by: Ingo Molnar <mingo@kernel.org>