Commit Graph

250 Commits

Author SHA1 Message Date
Linus Torvalds d4f4cf77b3 Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:

 - nommu updates from Afzal Mohammed cleaning up the vectors support

 - allow DMA memory "mapping" for nommu Benjamin Gaignard

 - fixing a correctness issue with R_ARM_PREL31 relocations in the
   module linker

 - add strlen() prototype for the decompressor

 - support for DEBUG_VIRTUAL from Florian Fainelli

 - adjusting memory bounds after memory reservations have been
   registered

 - unipher cache handling updates from Masahiro Yamada

 - initrd and Thumb Kconfig cleanups

* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (23 commits)
  ARM: mm: round the initrd reservation to page boundaries
  ARM: mm: clean up initrd initialisation
  ARM: mm: move initrd init code out of arm_memblock_init()
  ARM: 8655/1: improve NOMMU definition of pgprot_*()
  ARM: 8654/1: decompressor: add strlen prototype
  ARM: 8652/1: cache-uniphier: clean up active way setup code
  ARM: 8651/1: cache-uniphier: include <linux/errno.h> instead of <linux/types.h>
  ARM: 8650/1: module: handle negative R_ARM_PREL31 addends correctly
  ARM: 8649/2: nommu: remove Hivecs configuration is asm
  ARM: 8648/2: nommu: display vectors base
  ARM: 8647/2: nommu: dynamic exception base address setting
  ARM: 8646/1: mmu: decouple VECTORS_BASE from Kconfig
  ARM: 8644/1: Reduce "CPU: shutdown" message to debug level
  ARM: 8641/1: treewide: Replace uses of virt_to_phys with __pa_symbol
  ARM: 8640/1: Add support for CONFIG_DEBUG_VIRTUAL
  ARM: 8639/1: Define KERNEL_START and KERNEL_END
  ARM: 8638/1: mtd: lart: Rename partition defines to be prefixed with PART_
  ARM: 8637/1: Adjust memory boundaries after reservations
  ARM: 8636/1: Cleanup sanity_check_meminfo
  ARM: add CPU_THUMB_CAPABLE to indicate possible Thumb support
  ...
2017-02-28 11:50:53 -08:00
Russell King c466bda605 ARM: add CPU_THUMB_CAPABLE to indicate possible Thumb support
Clean up arch/arm/mm/Kconfig a little to provide a symbol which
indicates whether the CPU may support the Thumb instruction set.  This
gets rid of the growing dependencies on ARM_THUMB, and also gives us a
useful Kconfig symbol for choosing the kuser code.

Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-02-12 21:04:17 +00:00
Laura Abbott 0f5bf6d0af arch: Rename CONFIG_DEBUG_RODATA and CONFIG_DEBUG_MODULE_RONX
Both of these options are poorly named. The features they provide are
necessary for system security and should not be considered debug only.
Change the names to CONFIG_STRICT_KERNEL_RWX and
CONFIG_STRICT_MODULE_RWX to better describe what these options do.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Jessica Yu <jeyu@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-07 12:32:52 -08:00
Laura Abbott ad21fc4faa arch: Move CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX to be common
There are multiple architectures that support CONFIG_DEBUG_RODATA and
CONFIG_SET_MODULE_RONX. These options also now have the ability to be
turned off at runtime. Move these to an architecture independent
location and make these options def_bool y for almost all of those
arches.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-07 12:32:52 -08:00
Masahiro Yamada 01bf92788e ARM: 8623/1: mm: add ARM_L1_CACHE_SHIFT_7 for UniPhier outer cache
The UniPhier outer cache (arch/arm/mm/cache-uniphier.c) has 128 byte
line length and its tags are also managed per 128 byte line.  This
is very unfortunate, but the current 64 byte alignment for kmalloc()
causes sharing problems on DMA if used with this outer cache.

This commit adds ARM_L1_CACHE_SHIFT_7 to increase the DMA minimum
alignment to 128 byte if CACHE_UNIPHIER is enabled.  There are
several drivers that assume aligning to L1_CACHE_BYTES will be DMA
safe, so this commit also changes the L1_CACHE_BYTES for safety.

Having said that, I hesitate to align all the other SoCs in Multi
platform to the UniPhier's requirement.  So, I am disabling the
CONFIG_CACHE_UNIPHIER by default, so that multi_v7_defconfig will
still stay with CONFIG_ARM_L1_CACHE_SHIFT=6.  With this commit,
UniPhier SoCs will become slower, but it is much better than system
crash.  If desired, the outer-cache can be enabled by merge_config
or something.

Note:
The UniPhier PH1-Pro5 SoC is equipped also with L3 cache with 256
byte line size but its tags are managed per 128 byte sub-line.
So, ARM_L1_CACHE_SHIFT_7 should be fine for all the UniPhier SoCs.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-11-15 15:31:03 +00:00
Mark Rutland b828f96021 ARM: 8611/1: l2x0: add PMU support
The L2C-220 (AKA L220) and L2C-310 (AKA PL310) cache controllers feature
a Performance Monitoring Unit (PMU), which can be useful for tuning
and/or debugging. This hardware is always present and the relevant
registers are accessible to non-secure accesses. Thus, no special
firmware interface is necessary.

This patch adds support for the PMU, plugging into the usual perf
infrastructure. The overflow interrupt is not always available (e.g. on
RealView PBX A9 it is not wired up at all), and the hardware counters
saturate, so the driver does not make use of this. Instead, the driver
periodically polls and reset counters as required to avoid losing
events due to saturation.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Tested-by: Kim Phillips <kim.phillips@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-09-06 15:51:09 +01:00
Jonathan Austin bc0ee9d24a ARM: 8607/1: V7M: Wire up caches for V7M processors with cache support.
This patch does the plumbing required to invoke the V7M cache code added
in earlier patches in this series, although there is no users for that
yet.

In order to honour the I/D cache disable config options, this patch changes
the mechanism by which the CCR is set on boot, to be more like V7A/R.

Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Andras Szemzo <sza@esh.hu>
Tested-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-09-06 15:51:08 +01:00
Masahiro Yamada 520319de0c ARM: 8582/1: remove unused CONFIG_ARCH_HAS_BARRIERS
Since commit 2b749cb3a5 ("ARM: realview: remove private barrier
implementation"), this config is not used by any platform.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-07-02 11:01:08 +01:00
Zhaoxiu Zeng fff7fb0b2d lib/GCD.c: use binary GCD algorithm instead of Euclidean
The binary GCD algorithm is based on the following facts:
	1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
	2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
	3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)

Even on x86 machines with reasonable division hardware, the binary
algorithm runs about 25% faster (80% the execution time) than the
division-based Euclidian algorithm.

On platforms like Alpha and ARMv6 where division is a function call to
emulation code, it's even more significant.

There are two variants of the code here, depending on whether a fast
__ffs (find least significant set bit) instruction is available.  This
allows the unpredictable branches in the bit-at-a-time shifting loop to
be eliminated.

If fast __ffs is not available, the "even/odd" GCD variant is used.

I use the following code to benchmark:

	#include <stdio.h>
	#include <stdlib.h>
	#include <stdint.h>
	#include <string.h>
	#include <time.h>
	#include <unistd.h>

	#define swap(a, b) \
		do { \
			a ^= b; \
			b ^= a; \
			a ^= b; \
		} while (0)

	unsigned long gcd0(unsigned long a, unsigned long b)
	{
		unsigned long r;

		if (a < b) {
			swap(a, b);
		}

		if (b == 0)
			return a;

		while ((r = a % b) != 0) {
			a = b;
			b = r;
		}

		return b;
	}

	unsigned long gcd1(unsigned long a, unsigned long b)
	{
		unsigned long r = a | b;

		if (!a || !b)
			return r;

		b >>= __builtin_ctzl(b);

		for (;;) {
			a >>= __builtin_ctzl(a);
			if (a == b)
				return a << __builtin_ctzl(r);

			if (a < b)
				swap(a, b);
			a -= b;
		}
	}

	unsigned long gcd2(unsigned long a, unsigned long b)
	{
		unsigned long r = a | b;

		if (!a || !b)
			return r;

		r &= -r;

		while (!(b & r))
			b >>= 1;

		for (;;) {
			while (!(a & r))
				a >>= 1;
			if (a == b)
				return a;

			if (a < b)
				swap(a, b);
			a -= b;
			a >>= 1;
			if (a & r)
				a += b;
			a >>= 1;
		}
	}

	unsigned long gcd3(unsigned long a, unsigned long b)
	{
		unsigned long r = a | b;

		if (!a || !b)
			return r;

		b >>= __builtin_ctzl(b);
		if (b == 1)
			return r & -r;

		for (;;) {
			a >>= __builtin_ctzl(a);
			if (a == 1)
				return r & -r;
			if (a == b)
				return a << __builtin_ctzl(r);

			if (a < b)
				swap(a, b);
			a -= b;
		}
	}

	unsigned long gcd4(unsigned long a, unsigned long b)
	{
		unsigned long r = a | b;

		if (!a || !b)
			return r;

		r &= -r;

		while (!(b & r))
			b >>= 1;
		if (b == r)
			return r;

		for (;;) {
			while (!(a & r))
				a >>= 1;
			if (a == r)
				return r;
			if (a == b)
				return a;

			if (a < b)
				swap(a, b);
			a -= b;
			a >>= 1;
			if (a & r)
				a += b;
			a >>= 1;
		}
	}

	static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
		gcd0, gcd1, gcd2, gcd3, gcd4,
	};

	#define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))

	#if defined(__x86_64__)

	#define rdtscll(val) do { \
		unsigned long __a,__d; \
		__asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
		(val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \
	} while(0)

	static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
								unsigned long a, unsigned long b, unsigned long *res)
	{
		unsigned long long start, end;
		unsigned long long ret;
		unsigned long gcd_res;

		rdtscll(start);
		gcd_res = gcd(a, b);
		rdtscll(end);

		if (end >= start)
			ret = end - start;
		else
			ret = ~0ULL - start + 1 + end;

		*res = gcd_res;
		return ret;
	}

	#else

	static inline struct timespec read_time(void)
	{
		struct timespec time;
		clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
		return time;
	}

	static inline unsigned long long diff_time(struct timespec start, struct timespec end)
	{
		struct timespec temp;

		if ((end.tv_nsec - start.tv_nsec) < 0) {
			temp.tv_sec = end.tv_sec - start.tv_sec - 1;
			temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
		} else {
			temp.tv_sec = end.tv_sec - start.tv_sec;
			temp.tv_nsec = end.tv_nsec - start.tv_nsec;
		}

		return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
	}

	static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
								unsigned long a, unsigned long b, unsigned long *res)
	{
		struct timespec start, end;
		unsigned long gcd_res;

		start = read_time();
		gcd_res = gcd(a, b);
		end = read_time();

		*res = gcd_res;
		return diff_time(start, end);
	}

	#endif

	static inline unsigned long get_rand()
	{
		if (sizeof(long) == 8)
			return (unsigned long)rand() << 32 | rand();
		else
			return rand();
	}

	int main(int argc, char **argv)
	{
		unsigned int seed = time(0);
		int loops = 100;
		int repeats = 1000;
		unsigned long (*res)[TEST_ENTRIES];
		unsigned long long elapsed[TEST_ENTRIES];
		int i, j, k;

		for (;;) {
			int opt = getopt(argc, argv, "n:r:s:");
			/* End condition always first */
			if (opt == -1)
				break;

			switch (opt) {
			case 'n':
				loops = atoi(optarg);
				break;
			case 'r':
				repeats = atoi(optarg);
				break;
			case 's':
				seed = strtoul(optarg, NULL, 10);
				break;
			default:
				/* You won't actually get here. */
				break;
			}
		}

		res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
		memset(elapsed, 0, sizeof(elapsed));

		srand(seed);
		for (j = 0; j < loops; j++) {
			unsigned long a = get_rand();
			/* Do we have args? */
			unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
			unsigned long long min_elapsed[TEST_ENTRIES];
			for (k = 0; k < repeats; k++) {
				for (i = 0; i < TEST_ENTRIES; i++) {
					unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
					if (k == 0 || min_elapsed[i] > tmp)
						min_elapsed[i] = tmp;
				}
			}
			for (i = 0; i < TEST_ENTRIES; i++)
				elapsed[i] += min_elapsed[i];
		}

		for (i = 0; i < TEST_ENTRIES; i++)
			printf("gcd%d: elapsed %llu\n", i, elapsed[i]);

		k = 0;
		srand(seed);
		for (j = 0; j < loops; j++) {
			unsigned long a = get_rand();
			unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
			for (i = 1; i < TEST_ENTRIES; i++) {
				if (res[j][i] != res[j][0])
					break;
			}
			if (i < TEST_ENTRIES) {
				if (k == 0) {
					k = 1;
					fprintf(stderr, "Error:\n");
				}
				fprintf(stderr, "gcd(%lu, %lu): ", a, b);
				for (i = 0; i < TEST_ENTRIES; i++)
					fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
			}
		}

		if (k == 0)
			fprintf(stderr, "PASS\n");

		free(res);

		return 0;
	}

Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:

  zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
  gcd0: elapsed 10174
  gcd1: elapsed 2120
  gcd2: elapsed 2902
  gcd3: elapsed 2039
  gcd4: elapsed 2812
  PASS
  zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
  gcd0: elapsed 9309
  gcd1: elapsed 2280
  gcd2: elapsed 2822
  gcd3: elapsed 2217
  gcd4: elapsed 2710
  PASS
  zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
  gcd0: elapsed 9589
  gcd1: elapsed 2098
  gcd2: elapsed 2815
  gcd3: elapsed 2030
  gcd4: elapsed 2718
  PASS
  zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
  gcd0: elapsed 9914
  gcd1: elapsed 2309
  gcd2: elapsed 2779
  gcd3: elapsed 2228
  gcd4: elapsed 2709
  PASS

[akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 17:58:30 -07:00
Arnd Bergmann ac96680d22 ARM: 8535/1: mm: DEBUG_RODATA makes no sense with XIP_KERNEL
When CONFIG_DEBUG_ALIGN_RODATA is set, we get a link error:

arch/arm/mm/built-in.o:(.data+0x4bc): undefined reference to `__start_rodata_section_aligned'

However, this combination is useless, as XIP_KERNEL implies that all the
RODATA is already marked readonly, so both CONFIG_DEBUG_RODATA and
CONFIG_DEBUG_ALIGN_RODATA (which depends on the other) are not
needed with XIP_KERNEL, and this patches enforces that using a Kconfig
dependency.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 25362dc496 ("ARM: 8501/1: mm: flip priority of CONFIG_DEBUG_RODATA")
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-02-22 11:39:42 +00:00
Kees Cook 25362dc496 ARM: 8501/1: mm: flip priority of CONFIG_DEBUG_RODATA
The use of CONFIG_DEBUG_RODATA is generally seen as an essential part of
kernel self-protection:
http://www.openwall.com/lists/kernel-hardening/2015/11/30/13
Additionally, its name has grown to mean things beyond just rodata. To
get ARM closer to this, we ought to rearrange the names of the configs
that control how the kernel protects its memory. What was called
CONFIG_ARM_KERNMEM_PERMS is realy doing the work that other architectures
call CONFIG_DEBUG_RODATA.

This redefines CONFIG_DEBUG_RODATA to actually do the bulk of the
ROing (and NXing). In the place of the old CONFIG_DEBUG_RODATA, use
CONFIG_DEBUG_ALIGN_RODATA, since that's what the option does: adds
section alignment for making rodata explicitly NX, as arm does not split
the page tables like arm64 does without _ALIGN_RODATA.

Also adds human readable names to the sections so I could more easily
debug my typos, and makes CONFIG_DEBUG_RODATA default "y" for CPU_V7.

Results in /sys/kernel/debug/kernel_page_tables for each config state:

 # CONFIG_DEBUG_RODATA is not set
 # CONFIG_DEBUG_ALIGN_RODATA is not set

---[ Kernel Mapping ]---
0x80000000-0x80900000           9M     RW x  SHD
0x80900000-0xa0000000         503M     RW NX SHD

 CONFIG_DEBUG_RODATA=y
 CONFIG_DEBUG_ALIGN_RODATA=y

---[ Kernel Mapping ]---
0x80000000-0x80100000           1M     RW NX SHD
0x80100000-0x80700000           6M     ro x  SHD
0x80700000-0x80a00000           3M     ro NX SHD
0x80a00000-0xa0000000         502M     RW NX SHD

 CONFIG_DEBUG_RODATA=y
 # CONFIG_DEBUG_ALIGN_RODATA is not set

---[ Kernel Mapping ]---
0x80000000-0x80100000           1M     RW NX SHD
0x80100000-0x80a00000           9M     ro x  SHD
0x80a00000-0xa0000000         502M     RW NX SHD

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Laura Abbott <labbott@fedoraproject.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-02-08 15:56:45 +00:00
Arnd Bergmann 17d44d7d87 ARM: no longer make CPU targets visible separately
Now that realview and integrator always select the correct CPU
type themselves based on the core tiles, there is no need to
still have them user-visible in arch/arm/mm/Kconfig. The
ARM925T symbol has been selected by the only user for many
years, so that can be removed along with the realview and
integrator specific ones.

This also solves randconfig build problems on realview.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-18 14:09:21 +01:00
Arnd Bergmann 38541bf485 ARM: no longer force unbuffered DMA for realview
Commit 42c4dafe80 ("ARM: 6202/1: Do not ARM_DMA_MEM_BUFFERABLE
on RealView boards with L210/L220") changed the generic setting for
ARM_DMA_MEM_BUFFERABLE to be disabled on any Realview kernel that includes
support for any of the ARM11 variations. Doing this was required to
allow doing DMA without a lockup in the l2x0 cache controller on the
Realview platform.

Unfortunately, in a kernel that also contains support for any ARMv7
based machine, the same change makes it impossible to do DMA on ARMv7,
which gets in the way of enabling multiplatform support on Realview.

As confirmed by Catalin Marinas and Linus Walleij, the current
code for Realview that we have in the kernel does not actually
perform any DMA, and this is unlikely to change in the future.
Therefore we can revert 42c4dafe80 without introducing regressions,
but we must never start using DMA on this platform in the future.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:33 +01:00
Linus Torvalds 56e0464980 ARM: SoC platform updates for v4.4
New and/or improved SoC support for this release:
 
  - Marvell Berlin:
    * Enable standard DT-based cpufreq
    * Add CPU hotplug support
  - Freescale:
    * Ethernet init for i.MX7D
    * Suspend/resume support for i.MX6UL
  - Allwinner:
    * Support for R8 chipset (used on NTC's $9 C.H.I.P board)
  - Mediatek:
    * SMP support for some platforms
  - Uniphier:
    * L2 support
    * Cleaned up SMP support, etc.
 
 + A handful of other patches around above functionality, and a few other
 smaller changes.
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 -----END PGP SIGNATURE-----

Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC platform updates from Olof Johansson:
 "New and/or improved SoC support for this release:

  Marvell Berlin:
     - Enable standard DT-based cpufreq
     - Add CPU hotplug support

  Freescale:
     - Ethernet init for i.MX7D
     - Suspend/resume support for i.MX6UL

  Allwinner:
     - Support for R8 chipset (used on NTC's $9 C.H.I.P board)

  Mediatek:
     - SMP support for some platforms

  Uniphier:
     - L2 support
     - Cleaned up SMP support, etc.

  plus a handful of other patches around above functionality, and a few
  other smaller changes"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (42 commits)
  ARM: uniphier: rework SMP operations to use trampoline code
  ARM: uniphier: add outer cache support
  Documentation: EXYNOS: Update bootloader interface on exynos542x
  ARM: mvebu: add broken-idle option
  ARM: orion5x: use mac_pton() helper
  ARM: at91: pm: at91_pm_suspend_in_sram() must be 8-byte aligned
  ARM: sunxi: Add R8 support
  ARM: digicolor: select pinctrl/gpio driver
  arm: berlin: add CPU hotplug support
  arm: berlin: use non-self-cleared reset register to reset cpu
  ARM: mediatek: add smp bringup code
  ARM: mediatek: enable gpt6 on boot up to make arch timer working
  soc: mediatek: Fix random hang up issue while kernel init
  soc: ti: qmss: make acc queue support optional in the driver
  soc: ti: add firmware file name as part of the driver
  Documentation: dt: soc: Add description for knav qmss driver
  ARM: S3C64XX: Use PWM lookup table for mach-smartq
  ARM: S3C64XX: Use PWM lookup table for mach-hmt
  ARM: S3C64XX: Use PWM lookup table for mach-crag6410
  ARM: S3C64XX: Use PWM lookup table for smdk6410
  ...
2015-11-10 14:56:23 -08:00
Masahiro Yamada e7ecbc057b ARM: uniphier: add outer cache support
This commit adds support for UniPhier outer cache controller.
All the UniPhier SoCs are equipped with the L2 cache, while the L3
cache is currently only integrated on PH1-Pro5 SoC.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-10-27 09:20:50 +09:00
Russell King db695c0509 ARM: remove user cmpxchg syscall
Mark Brand reports that a NEEDS_SYSCALL_FOR_CMPXCHG enabled kernel would
open a security hole in the ghost syscall used to implement cmpxchg, as
it fails to validate the user pointer.

However, in order for this option to be enabled, you'd need to be
building a pre-ARMv6 kernel with SMP support.  There is only one system
known which fits that, which is an early ARM SMP FPGA implementation
based on the ARM926T.

In any case, the Kconfig does not allow SMP to be enabled for pre-ARMv6
systems.

Moreover, even if NEEDS_SYSCALL_FOR_CMPXCHG were to be enabled, the
kernel would not build as __ARM_NR_cmpxchg64 is not defined.

The simple answer is to remove the buggy code.

Reported-by: Mark Brand <markbrand@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-03 16:36:45 +01:00
Russell King f81309067f ARM: move heavy barrier support out of line
The existing memory barrier macro causes a significant amount of code
to be inserted inline at every call site.  For example, in
gpio_set_irq_type(), we have this for mb():

c0344c08:       f57ff04e        dsb     st
c0344c0c:       e59f8190        ldr     r8, [pc, #400]  ; c0344da4 <gpio_set_irq_type+0x230>
c0344c10:       e3590004        cmp     r9, #4
c0344c14:       e5983014        ldr     r3, [r8, #20]
c0344c18:       0a000054        beq     c0344d70 <gpio_set_irq_type+0x1fc>
c0344c1c:       e3530000        cmp     r3, #0
c0344c20:       0a000004        beq     c0344c38 <gpio_set_irq_type+0xc4>
c0344c24:       e50b2030        str     r2, [fp, #-48]  ; 0xffffffd0
c0344c28:       e50bc034        str     ip, [fp, #-52]  ; 0xffffffcc
c0344c2c:       e12fff33        blx     r3
c0344c30:       e51bc034        ldr     ip, [fp, #-52]  ; 0xffffffcc
c0344c34:       e51b2030        ldr     r2, [fp, #-48]  ; 0xffffffd0
c0344c38:       e5963004        ldr     r3, [r6, #4]

Moving the outer_cache_sync() call out of line reduces the impact of
the barrier:

c0344968:       f57ff04e        dsb     st
c034496c:       e35a0004        cmp     sl, #4
c0344970:       e50b2030        str     r2, [fp, #-48]  ; 0xffffffd0
c0344974:       0a000044        beq     c0344a8c <gpio_set_irq_type+0x1b8>
c0344978:       ebf363dd        bl      c001d8f4 <arm_heavy_mb>
c034497c:       e5953004        ldr     r3, [r5, #4]

This should reduce the cache footprint of this code.  Overall, this
results in a reduction of around 20K in the kernel size:

    text    data      bss      dec     hex filename
10773970  667392 10369656 21811018 14ccf4a ../build/imx6/vmlinux-old
10754219  667392 10369656 21791267 14c8223 ../build/imx6/vmlinux-new

Another advantage to this approach is that we can finally resolve the
issue of SoCs which have their own memory barrier requirements within
multiplatform kernels (such as OMAP.)  Here, the bus interconnects
need additional handling to ensure that writes become visible in the
correct order (eg, between dma_map() operations, writes to DMA
coherent memory, and MMIO accesses.)

Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-25 15:28:05 +01:00
Russell King 9de44aa4dc Merge branches 'arnd-fixes', 'clk', 'misc', 'v7' and 'fixes' into for-next 2015-06-12 21:18:08 +01:00
Stefan Agner 45b0fa09c6 ARM: 8369/1: ARMv7M: define size of vector table for Vybrid
Vybrids has 112 peripheral interrupts which can be routed to the
Cortex-M4's NVIC interrupt controller.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-02 09:58:19 +01:00
Russell King d8dc7fbd53 ARM: re-implement physical address space switching
Re-implement the physical address space switching to be architecturally
compliant.  This involves flushing the caches, disabling the MMU, and
only then updating the page tables.  Once that is complete, the system
can be brought back up again.

Since we disable the MMU, we need to do the update in assembly code.
Luckily, the entries which need updating are fairly trivial, and are
all setup by the early assembly code.  We can merely adjust each entry
by the delta required.

Not only does this fix the code to be architecturally compliant, but it
fixes a couple of bugs too:

1. The original code would only ever update the first L2 entry covering
   a fraction of the kernel; the remainder were left untouched.
2. The L2 entries covering the DTB blob were likewise untouched.

This solution fixes up all entries.

Tested-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-01 23:46:33 +01:00
Arnd Bergmann c32b765572 ARM: 8374/1: no longer expose CPU_ARM7TDMI/CPU_ARM9TDMI
Atmel at91x40 is gone, so we no longer have any platform using
either of these two, and we get randconfig failures on NOMMU
kernels if they accidentally get enabled on something that conflicts
with ARMv4T.

This stops short of removing the entire CPU support for now,
but as nothing selects these, it is basically dead code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-28 00:29:14 +01:00
Maxime Coquelin stm32 6b1814cde5 ARM: 8340/1: ARMv7-M: Enlarge vector table up to 256 entries
From Cortex-M reference manuals, the nvic supports up to 240 interrupts.
So the number of entries in vectors table is up to 256.

This patch adds a new config flag to specify the number of external interrupts.
Some ifdeferies are added in order to respect the natural alignment without
wasting too much space on smaller systems.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Stefan Agner <stefan@agner.ch>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-08 10:42:21 +01:00
Russell King 6b7acae74f Merge branches 'misc' and 'vdso' into for-next 2015-04-23 21:05:16 +00:00
Nathan Lynch 5d38000b3c ARM: 8342/1: VDSO: depend on CPU_V7
When targeting ARMv3 (e.g. rpc) and enabling CONFIG_VDSO we get:

arch/arm/vdso/datapage.S:13: Error: selected processor does not
support ARM mode `bx lr'

One fix considered was to use 'ldr pc,lr' for such configurations, but
since the VDSO is unlikely to be useful for pre-v7 hardware, just make
it depend on CONFIG_CPU_V7.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-18 00:23:25 +01:00
Russell King c848791f03 Merge branches 'misc', 'vdso' and 'fixes' into for-next
Conflicts:
	arch/arm/mm/proc-macros.S
2015-04-14 22:28:25 +01:00
Florian Fainelli e1e2f6e4c5 ARM: 8276/1: Make CPU_DCACHE_DISABLE depend on !SMP
Enabling CPU_DCACHE_DISABLE on a SMP capable system will prevent the
kernel from booting because of the following ldrex instruction in
arch_spin_lock:

(gdb) x/10i $pc
=> 0xc053cfa8 <_raw_spin_lock+4>:       ldrex   r3, [r0]
   0xc053cfac <_raw_spin_lock+8>:       add     r2, r3, #65536  ; 0x10000

which is taken by the very first printk call:

    at /home/fainelli/work/linux/arch/arm/include/asm/spinlock.h:65
    fmt=0xc0637650 " 01 66Booting Linux on physical CPU 0x%xn", args=<incomplete type>)
    at kernel/printk/printk.c:1525
    fmt=0xc05370f4 <printk+52> " 24320215342 04340235344 20320215342 36377/341 17") at kernel/printk/printk.c:1688

ldrex requires exclusive monitor(s) (local or global) which are no longer
working when the Data cache is disabled in CP15 and will just hang the CPU
there.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-02 10:06:35 +01:00
Nathan Lynch e5b61deb3a ARM: 8332/1: add CONFIG_VDSO Kconfig and Makefile bits
Allow users to enable the vdso in Kconfig; include the vdso in the
build if CONFIG_VDSO is enabled.  Add 'vdso_install' target.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-27 22:20:45 +00:00
Paul Bolle d88d6cfc91 ARM: mm: Remove Kconfig symbol CACHE_PL310
Commit 20e783e39e ("ARM: 8296/1: cache-l2x0: clean up aurora cache
handling") removed the only user of the Kconfig symbol CACHE_PL310.
Setting CACHE_PL310 is now pointless. Remove its Kconfig entry, and one
select of this symbol.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-02-18 12:24:29 +01:00
Arnd Bergmann fba289054f ARM: 8298/1: ARM_KERNMEM_PERMS only works with MMU enabled
The recently added ARM_KERNMEM_PERMS feature works by manipulating
the kernel page tables, which obviously requires an MMU. Trying
to enable this feature when the MMU is disabled results in a lot
of compile errors in mm/init.c, so let's add a Kconfig dependency
to avoid that case.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-01-29 15:23:31 +00:00
Linus Torvalds 26ceb127f7 Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
 "The major updates included in this update are:

   - Clang compatible stack pointer accesses by Behan Webster.
   - SA11x0 updates from Dmitry Eremin-Solenikov.
   - kgdb handling of breakpoints with read-only text/modules
   - Support for Privileged-no-execute feature on ARMv7 to prevent
     userspace code execution by the kernel.
   - AMBA primecell bus handling of irq-safe runtime PM
   - Unwinding support for memset/memzero/memmove/memcpy functions
   - VFP fixes for Krait CPUs and improvements in detecting the VFP
     architecture
   - A number of code cleanups (using pr_*, removing or reducing the
     severity of a couple of kernel messages, splitting ftrace asm code
     out to a separate file, etc.)
   - Add machine name to stack dump output"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (62 commits)
  ARM: 8247/2: pcmcia: sa1100: make use of device clock
  ARM: 8246/2: pcmcia: sa1111: provide device clock
  ARM: 8245/1: pcmcia: soc-common: enable/disable socket clocks
  ARM: 8244/1: fbdev: sa1100fb: make use of device clock
  ARM: 8243/1: sa1100: add a clock alias for sa1111 pcmcia device
  ARM: 8242/1: sa1100: add cpu clock
  ARM: 8221/1: PJ4: allow building in Thumb-2 mode
  ARM: 8234/1: sa1100: reorder IRQ handling code
  ARM: 8233/1: sa1100: switch to hwirq usage
  ARM: 8232/1: sa1100: merge GPIO multiplexer IRQ to "normal" irq domain
  ARM: 8231/1: sa1100: introduce irqdomains support
  ARM: 8230/1: sa1100: shift IRQs by one
  ARM: 8229/1: sa1100: replace irq numbers with names in irq driver
  ARM: 8228/1: sa1100: drop entry-macro.S
  ARM: 8227/1: sa1100: switch to MULTI_IRQ_HANDLER
  ARM: 8241/1: Update processor_modes for hyp and monitor mode
  ARM: 8240/1: MCPM: document mcpm_sync_init()
  ARM: 8239/1: Introduce {set,clear}_pte_bit
  ARM: 8238/1: mm: Refine set_memory_* functions
  ARM: 8237/1: fix flush_pfn_alias
  ...
2014-12-12 15:26:48 -08:00
Linus Torvalds 6cd94d5e57 ARM: SoC platform changes for 3.19
New and updated SoC support, notable changes include:
 
 * bcm: brcmstb SMP support
 * bcm: initial iproc/cygnus support
 * exynos: Exynos4415 SoC support
 * exynos: PMU and suspend support for Exynos5420
 * exynos: PMU support for Exynos3250
 * exynos: pm related maintenance
 * imx: new LS1021A SoC support
 * imx: vybrid 610 global timer support
 * integrator: convert to using multiplatform configuration
 * mediatek: earlyprintk support for mt8127/mt8135
 * meson: meson8 soc and l2 cache controller support
 * mvebu: Armada 38x CPU hotplug support
 * mvebu: drop support for prerelease Armada 375 Z1 stepping
 * mvebu: extended suspend support, now works on Armada 370/XP
 * omap: hwmod related maintenance
 * omap: prcm cleanup
 * pxa: initial pxa27x DT handling
 * rockchip: SMP support for rk3288
 * rockchip: add cpu frequency scaling support
 * shmobile: r8a7740 power domain support
 * shmobile: various small restart, timer, pci apmu changes
 * sunxi: Allwinner A80 (sun9i) earlyprintk support
 * ux500: power domain support
 
 Overall, a significant chunk of changes, coming mostly from
 the usual suspects: omap, shmobile, samsung and mvebu, all of
 which already contain a lot of platform specific code in
 arch/arm.
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Merge tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC platform changes from Arnd Bergmann:
 "New and updated SoC support, notable changes include:

   - bcm:
        brcmstb SMP support
        initial iproc/cygnus support
   - exynos:
        Exynos4415 SoC support
        PMU and suspend support for Exynos5420
        PMU support for Exynos3250
        pm related maintenance
   - imx:
        new LS1021A SoC support
        vybrid 610 global timer support
   - integrator:
        convert to using multiplatform configuration
   - mediatek:
        earlyprintk support for mt8127/mt8135
   - meson:
        meson8 soc and l2 cache controller support
   - mvebu:
        Armada 38x CPU hotplug support
        drop support for prerelease Armada 375 Z1 stepping
        extended suspend support, now works on Armada 370/XP
   - omap:
        hwmod related maintenance
        prcm cleanup
   - pxa:
        initial pxa27x DT handling
   - rockchip:
        SMP support for rk3288
        add cpu frequency scaling support
   - shmobile:
        r8a7740 power domain support
        various small restart, timer, pci apmu changes
   - sunxi:
        Allwinner A80 (sun9i) earlyprintk support
   - ux500:
        power domain support

  Overall, a significant chunk of changes, coming mostly from the usual
  suspects: omap, shmobile, samsung and mvebu, all of which already
  contain a lot of platform specific code in arch/arm"

* tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (187 commits)
  ARM: mvebu: use the cpufreq-dt platform_data for independent clocks
  soc: integrator: Add terminating entry for integrator_cm_match
  ARM: mvebu: add SDRAM controller description for Armada XP
  ARM: mvebu: adjust mbus controller description on Armada 370/XP
  ARM: mvebu: add suspend/resume DT information for Armada XP GP
  ARM: mvebu: synchronize secondary CPU clocks on resume
  ARM: mvebu: make sure MMU is disabled in armada_370_xp_cpu_resume
  ARM: mvebu: Armada XP GP specific suspend/resume code
  ARM: mvebu: reserve the first 10 KB of each memory bank for suspend/resume
  ARM: mvebu: implement suspend/resume support for Armada XP
  clk: mvebu: add suspend/resume for gatable clocks
  bus: mvebu-mbus: provide a mechanism to save SDRAM window configuration
  bus: mvebu-mbus: suspend/resume support
  clocksource: time-armada-370-xp: add suspend/resume support
  irqchip: armada-370-xp: Add suspend/resume support
  ARM: add lolevel debug support for asm9260
  ARM: add mach-asm9260
  ARM: EXYNOS: use u8 for val[] in struct exynos_pmu_conf
  power: reset: imx-snvs-poweroff: add power off driver for i.mx6
  ARM: imx: temporarily remove CONFIG_SOC_FSL from LS1021A
  ...
2014-12-09 14:38:28 -08:00
Russell King e9f2d6d660 Merge branch 'devel-stable' into for-next 2014-12-05 16:30:54 +00:00
Nathan Lynch 08b964ff3c ARM: 8198/1: make kuser helpers depend on MMU
The kuser helpers page is not set up on non-MMU systems, so it does
not make sense to allow CONFIG_KUSER_HELPERS to be enabled when
CONFIG_MMU=n.  Allowing it to be set on !MMU results in an oops in
set_tls (used in execve and the arm_syscall trap handler):

Unhandled exception: IPSR = 00000005 LR = fffffff1
CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216
task: 8b838000 ti: 8b82a000 task.ti: 8b82a000
PC is at flush_thread+0x32/0x40
LR is at flush_thread+0x21/0x40
pc : [<8f00157a>]    lr : [<8f001569>]    psr: 4100000b
sp : 8b82be20  ip : 00000000  fp : 8b83c000
r10: 00000001  r9 : 88018c84  r8 : 8bb85000
r7 : 8b838000  r6 : 00000000  r5 : 8bb77400  r4 : 8b82a000
r3 : ffff0ff0  r2 : 8b82a000  r1 : 00000000  r0 : 88020354
xPSR: 4100000b
CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216
[<8f002bc1>] (unwind_backtrace) from [<8f002033>] (show_stack+0xb/0xc)
[<8f002033>] (show_stack) from [<8f00265b>] (__invalid_entry+0x4b/0x4c)

As best I can tell this issue existed for the set_tls ARM syscall
before commit fbfb872f5f "ARM: 8148/1: flush TLS and thumbee
register state during exec" consolidated the TLS manipulation code
into the set_tls helper function, but now that we're using it to flush
register state during execve, !MMU users encounter the oops at the
first exec.

Prevent CONFIG_MMU=n configurations from enabling
CONFIG_KUSER_HELPERS.

Fixes: fbfb872f5f (ARM: 8148/1: flush TLS and thumbee register state during exec)

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Reported-by: Stefan Agner <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-13 23:45:21 +00:00
Linus Walleij dc680b989d ARM: fix multiplatform allmodcompile
Commit 68f3b875f7
"ARM: integrator: make the Integrator multiplatform"
broke allmodconfig like this:

>> arch/arm/include/asm/cmpxchg.h:114:2: error: #error
"SMP is not supported on this platform"
(etc)

This is due to the fact that as we turned on multiplatform
for the Integrator, this enabled a lot of non-applicable
CPU's to be selected for its multiplatform images, due to
a lot of "depends on ARCH_INTEGRATOR" restrictions in
arch/arm/mm/Kconfig for the different ARM CPU types.

Fix this by restricting the CPU selections to respective
multiplatform config, which now becomes a subset of the
possible Integrator configurations, or alternatively the
non-multiplatform config plus ARCH_INTEGRATOR, i.e.:

if (!ARCH_MULTIPLATFORM || ARCH_MULTI_Vx) &&
   (ARCH_INTEGRATOR || ARCH_FOO ...)

Since the Integrator has been converted to multiplatform,
this will often take the short form:

if (ARCH_MULTI_Vx && ARCH_INTEGRATOR)

If no other non-multiplatform platforms are elegible.

Reported-by: Build bot for Mark Brown <broonie@kernel.org>
Reported-by: Kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2014-11-11 20:14:07 +01:00
Kees Cook 80d6b0c2ee ARM: mm: allow text and rodata sections to be read-only
This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata
read-only. Additionally, this splits rodata from text so that rodata can
also be NX, which may lead to wasted memory when aligning to SECTION_SIZE.
The read-only areas are made writable during ftrace updates and kexec.

Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16 14:38:54 -07:00
Kees Cook 1e6b48116a ARM: mm: allow non-text sections to be non-executable
Adds CONFIG_ARM_KERNMEM_PERMS to separate the kernel memory regions
into section-sized areas that can have different permisions. Performs
the NX permission changes during free_initmem, so that init memory can be
reclaimed.

This uses section size instead of PMD size to reduce memory lost to
padding on non-LPAE systems.

Based on work by Brad Spengler, Larry Bassel, and Laura Abbott.

Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16 14:38:54 -07:00
Linus Torvalds b3345d7c57 ARM: SoC platform changes for 3.17
This is the bulk of new SoC enablement and other platform changes for 3.17:
 
 * Samsung S5PV210 has been converted to DT and multiplatform
 * Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms
 * Kirkwood, one of the popular Marvell platforms, is folded into the
   mvebu platform code, removing mach-kirkwood.
 * Hwmod data for TI AM43xx and DRA7 platforms.
 * More additions of Renesas shmobile platform support
 * Removal of plat-samsung contents that can be removed with S5PV210 being
   multiplatform/DT-enabled and the other two old platforms being removed.
 
 New platforms (most with only basic support right now):
 
 * Hisilicon X5HD2 settop box chipset is introduced
 * Mediatek MT6589 (mobile chipset) is introduced
 * Broadcom BCM7xxx settop box chipset is introduced
 
 + as usual a lot other pieces all over the platform code.
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Merge tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC platform changes from Olof Johansson:
 "This is the bulk of new SoC enablement and other platform changes for
  3.17:

   - Samsung S5PV210 has been converted to DT and multiplatform
   - Clock drivers and bindings for some of the lower-end i.MX 1/2
     platforms
   - Kirkwood, one of the popular Marvell platforms, is folded into the
     mvebu platform code, removing mach-kirkwood
   - Hwmod data for TI AM43xx and DRA7 platforms
   - More additions of Renesas shmobile platform support
   - Removal of plat-samsung contents that can be removed with S5PV210
     being multiplatform/DT-enabled and the other two old platforms
     being removed

  New platforms (most with only basic support right now):

   - Hisilicon X5HD2 settop box chipset is introduced
   - Mediatek MT6589 (mobile chipset) is introduced
   - Broadcom BCM7xxx settop box chipset is introduced

  + as usual a lot other pieces all over the platform code"

* tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits)
  ARM: hisi: remove smp from machine descriptor
  power: reset: move hisilicon reboot code
  ARM: dts: Add hix5hd2-dkb dts file.
  ARM: debug: Rename Hi3716 to HIX5HD2
  ARM: hisi: enable hix5hd2 SoC
  ARM: hisi: add ARCH_HISI
  MAINTAINERS: add entry for Broadcom ARM STB architecture
  ARM: brcmstb: select GISB arbiter and interrupt drivers
  ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs
  ARM: configs: enable SMP in bcm_defconfig
  ARM: add SMP support for Broadcom mobile SoCs
  Documentation: arm: misc updates to Marvell EBU SoC status
  Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC
  ARM: mvebu: fix build without platforms selected
  ARM: mvebu: add cpuidle support for Armada 38x
  ARM: mvebu: add cpuidle support for Armada 370
  cpuidle: mvebu: add Armada 38x support
  cpuidle: mvebu: add Armada 370 support
  cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7
  ARM: mvebu: export the SCU address
  ...
2014-08-08 11:14:29 -07:00
Russell King c89c3a6acb Merge branch 'swp' (early part) into for-next 2014-08-05 10:27:17 +01:00
Olof Johansson 4338925434 mvebu SoC changes for v3.17 (round 2)
- kirkwood
    - Remove mach-kirkwood/, It's fully supported in mach-mvebu/
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Merge tag 'mvebu-soc-3.17-2' of git://git.infradead.org/linux-mvebu into next/soc

Merge "ARM: mvebu SoC changes for v3.17 (round 2)" from Jason Cooper:

"Yeah, it's just one patch, but it's a beautiful one!  Thanks to the
efforts of many people over the last couple years, and in particular,
Andrew Lunn, Kirkwood has been completely converted to DT."

 - kirkwood
   * Remove mach-kirkwood/, It's fully supported in mach-mvebu/

* tag 'mvebu-soc-3.17-2' of git://git.infradead.org/linux-mvebu:
  ARM: Kirkwood: Remove mach-kirkwood

Signed-off-by: Olof Johansson <olof@lixom.net>
2014-07-19 14:28:06 -07:00
Russell King a11dd731f5 ARM: SWP emulation: always enable when SMP is enabled
SWP is deprecated in ARMv6 and ARMv7 CPUs, but more importantly, when
running on a SMP system, SWP doesn't guarantee atomicity.  This means
it can't really be used (by userspace) for locking purposes in a SMP
environment.

Currently, many configurations leave the SWP emulation disabled, which
means we never know if userspace executes this instruction on ARMv7
hardware.  Rectify this by enabling SWP emulation for ARMv7 with SMP
(where we can trap the instruction.)

Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 12:29:47 +01:00
Shawn Guo 80d3cb9132 ARM: 8090/1: add revision info for PL310 errata 588369 and 727915
Add revision info for PL310_ERRATA_588369 and PL310_ERRATA_727915 to
help people understand if they need to enable the errata for their
hardware.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 12:29:26 +01:00
Andrew Lunn ba364fc752 ARM: Kirkwood: Remove mach-kirkwood
Now that all boards have been converted to DT and all the support code
lives in mach-mvebu, we can remove mach-kirkwood.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lkml.kernel.org/r/1405028192-9623-2-git-send-email-andrew@lunn.ch
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-07-13 22:13:39 +00:00
Russell King a641f3a6ab ARM: l2c: fix dependencies on PL310 errata symbols
A number of configurations spit out warnings similar to:

warning: (SOC_IMX6 && SOC_VF610 && ARCH_OMAP4) selects PL310_ERRATA_588369 which has unmet direct dependencies (CACHE_L2X0)
warning: (SOC_IMX6 && SOC_VF610 && ARCH_OMAP4) selects PL310_ERRATA_727915 which has unmet direct dependencies (CACHE_L2X0)

Clean up the dependencies here:
* PL310 symbols should only be selected when CACHE_L2X0 is enabled.
* Since the cache-l2x0 code detects PL310 presence at runtime, and we will
  eventually get rid of CACHE_PL310, surround these errata options with an
  if CACHE_L2X0 conditional rather than repeating the dependency against
  each.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-19 11:29:28 +01:00
Russell King c0fe18ba30 ARM: l2c: move errata configuration options to arch/arm/mm/Kconfig
Move the L2C-310 errata configuration options to arch/arm/mm/Kconfig
along side the option which enables support for this device.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-05-30 00:48:37 +01:00
Russell King 51aaf81fae ARM: keep arch/arm/Kconfig and arch/arm/mm/Kconfig select entries sorted
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-23 09:31:10 +01:00
Linus Torvalds ff050ad12c ARM: SoC specific changes
Lots of changes specific to one of the SoC families. Some that
 stick out are:
 
 * mach-qcom gains new features, most importantly SMP support for
   the newer chips (Stephen Boyd, Rohit Vaswani)
 * mvebu gains support for three new SoCs: Armada 375, 380 and 385
   (Thomas Petazzoni and Free-electrons team)
 * SMP support for Rockchips (Heiko Stübner)
 * Lots of i.MX changes (Shawn Guo)
 * Added support for BCM5301x SoC (Hauke Mehrtens)
 * Multiplatform support for Marvell Kirkwood and Dove
   (Andrew Lunn and Sebastian Hesselbarth doing the final part
   of a long journey)
 * Unify davinci platforms and remove obsolete ones (Sekhar Nori,
   Arnd Bergmann)
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Merge tag 'soc-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC specific changes from Arnd Bergmann:
 "Lots of changes specific to one of the SoC families.  Some that stick
  out are:

   - mach-qcom gains new features, most importantly SMP support for the
     newer chips (Stephen Boyd, Rohit Vaswani)
   - mvebu gains support for three new SoCs: Armada 375, 380 and 385
     (Thomas Petazzoni and Free-electrons team)
   - SMP support for Rockchips (Heiko Stübner)
   - Lots of i.MX changes (Shawn Guo)
   - Added support for BCM5301x SoC (Hauke Mehrtens)
   - Multiplatform support for Marvell Kirkwood and Dove (Andrew Lunn
     and Sebastian Hesselbarth doing the final part of a long journey)
   - Unify davinci platforms and remove obsolete ones (Sekhar Nori, Arnd
     Bergmann)"

* tag 'soc-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (126 commits)
  ARM: sunxi: Select HAVE_ARM_ARCH_TIMER
  ARM: cache-tauros2: remove ARMv6 code
  ARM: mvebu: don't select CONFIG_NEON
  ARM: davinci: fix DT booting with default defconfig
  ARM: configs: bcm_defconfig: enable bcm590xx regulator support
  ARM: davinci: remove tnetv107x support
  MAINTAINERS: Update ARM STi maintainers
  ARM: restrict BCM_KONA_UART to ARCH_BCM_MOBILE
  ARM: bcm21664: Add board support.
  ARM: sunxi: Add the new watchog compatibles to the reboot code
  ARM: enable ARM_HAS_SG_CHAIN for multiplatform
  ARM: davinci: remove da8xx_omapl_defconfig
  ARM: davinci: da8xx: fix multiple watchdog device registration
  ARM: davinci: add da8xx specific configs to davinci_all_defconfig
  ARM: davinci: enable da8xx build concurrently with older devices
  ARM: BCM5301X: workaround suppress fault
  ARM: BCM5301X: add early debugging support
  ARM: BCM5301X: initial support for the BCM5301X/BCM470X SoCs with ARM CPU
  ARM: mach-bcm: Remove GENERIC_TIME
  ARM: shmobile: APMU: Fix warnings due to improper printk formats
  ...
2014-04-05 14:19:54 -07:00
Linus Torvalds 9f800363bb ARM: SoC non-critical bug fixes for 3.15
Lots of isolated bug fixes that were not found to be important
 enough to be submitted before the merge window or backported
 into stable kernels.
 The vast majority of these came out of Arnd's randconfig testing
 and just prevents running into build-time bugs in configurations
 that we do not care about in practice.
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Merge tag 'fixes-non-critical-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC non-critical bug fixes from Arnd Bergmann:
 "Lots of isolated bug fixes that were not found to be important enough
  to be submitted before the merge window or backported into stable
  kernels.

  The vast majority of these came out of Arnd's randconfig testing and
  just prevents running into build-time bugs in configurations that we
  do not care about in practice"

* tag 'fixes-non-critical-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (75 commits)
  ARM: at91: fix a typo
  ARM: moxart: fix CPU selection
  ARM: tegra: fix board DT pinmux setup
  ARM: nspire: Fix compiler warning
  IXP4xx: Fix DMA masks.
  Revert "ARM: ixp4xx: Make dma_set_coherent_mask common, correct implementation"
  IXP4xx: Fix Goramo Multilink GPIO conversion.
  Revert "ARM: ixp4xx: fix gpio rework"
  ARM: tegra: make debug_ll code build for ARMv6
  ARM: sunxi: fix build for THUMB2_KERNEL
  ARM: exynos: add missing include of linux/module.h
  ARM: exynos: fix l2x0 saved regs handling
  ARM: samsung: select CRC32 for SAMSUNG_PM_CHECK
  ARM: samsung: select ATAGS where necessary
  ARM: samsung: fix SAMSUNG_PM_DEBUG Kconfig logic
  ARM: samsung: allow serial driver to be disabled
  ARM: s5pv210: enable IDE support in MACH_TORBRECK
  ARM: s5p64x0: fix building with only one soc type
  ARM: s3c64xx: select power domains only when used
  ARM: s3c64xx: MACH_SMDK6400 needs HSMMC1
  ...
2014-04-05 13:44:27 -07:00
Arnd Bergmann fa04e209ae ARM: rpc: autoselect CPU_SA110
ARCH_RPC no longer supports other CPUs aside from StrongARM110,
so we can make the option implicitly selected by the platform
and no longer give the option of building a kernel without CPU
support.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
2014-03-21 18:26:07 +01:00
Andrew Lunn adc00979a8 ARM: MM Enable building Feroceon L2 cache controller with ARCH_MVEBU
Kirkwood, which uses the Feroceon L2 cache controller will soon be
moving into mach-mvebu. Allow the cache controller to be built in this
situation.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-02-22 21:19:53 +00:00
Will Deacon b6ccb9803e ARM: 7954/1: mm: remove remaining domain support from ARMv6
CPU_32v6 currently selects CPU_USE_DOMAINS if CPU_V6 and MMU. This is
because ARM 1136 r0pX CPUs lack the v6k extensions, and therefore do
not have hardware thread registers. The lack of these registers requires
the kernel to update the vectors page at each context switch in order to
write a new TLS pointer. This write must be done via the userspace
mapping, since aliasing caches can lead to expensive flushing when using
kmap. Finally, this requires the vectors page to be mapped r/w for
kernel and r/o for user, which has implications for things like put_user
which must trigger CoW appropriately when targetting user pages.

The upshot of all this is that a v6/v7 kernel makes use of domains to
segregate kernel and user memory accesses. This has the nasty
side-effect of making device mappings executable, which has been
observed to cause subtle bugs on recent cores (e.g. Cortex-A15
performing a speculative instruction fetch from the GIC and acking an
interrupt in the process).

This patch solves this problem by removing the remaining domain support
from ARMv6. A new memory type is added specifically for the vectors page
which allows that page (and only that page) to be mapped as user r/o,
kernel r/w. All other user r/o pages are mapped also as kernel r/o.
Patch co-developed with Russell King.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-10 11:48:13 +00:00