linux-stable.git/arch/powerpc/kernel/prom.c, branch linux-3.10.y

powerpc: scan_features() updates incorrect bits for REAL_LE

2016-06-07T08:42:53+00:00

commit 6997e57d693b07289694239e52a10d2f02c3a46f upstream.

The REAL_LE feature entry in the ibm_pa_feature struct is missing an MMU
feature value, meaning all the remaining elements initialise the wrong
values.

This means instead of checking for byte 5, bit 0, we check for byte 0,
bit 0, and then we incorrectly set the CPU feature bit as well as MMU
feature bit 1 and CPU user feature bits 0 and 2 (5).

Checking byte 0 bit 0 (IBM numbering), means we're looking at the
"Memory Management Unit (MMU)" feature - ie. does the CPU have an MMU.
In practice that bit is set on all platforms which have the property.

This means we set CPU_FTR_REAL_LE always. In practice that seems not to
matter because all the modern cpus which have this property also
implement REAL_LE, and we've never needed to disable it.

We're also incorrectly setting MMU feature bit 1, which is:

#define MMU_FTR_TYPE_8xx 0x00000002

Luckily the only place that looks for MMU_FTR_TYPE_8xx is in Book3E
code, which can't run on the same cpus as scan_features(). So this also
doesn't matter in practice.

Finally in the CPU user feature mask, we're setting bits 0 and 2. Bit 2
is not currently used, and bit 0 is:

#define PPC_FEATURE_PPC_LE 0x00000001

Which says the CPU supports the old style "PPC Little Endian" mode.
Again this should be harmless in practice as no 64-bit CPUs implement
that mode.

Fix the code by adding the missing initialisation of the MMU feature.

Also add a comment marking CPU user feature bit 2 (0x4) as reserved. It
would be unsafe to start using it as old kernels incorrectly set it.

Fixes: 44ae3ab3358e ("powerpc: Free up some CPU feature bits by moving out MMU-related features")
Signed-off-by: Anton Blanchard
[mpe: Flesh out changelog, add comment reserving 0x4]
Signed-off-by: Michael Ellerman
Signed-off-by: Greg Kroah-Hartman
Signed-off-by: Willy Tarreau

Merge branch 'dt' into next

2012-11-15T04:02:44+00:00

powerpc: Add asm/debug.h to get powerpc_debugfs_root

2012-11-15T01:59:27+00:00

Since the "Disintegrate asm/system.h for PowerPC"
(ae3a197e3d0bfe3f4bf1693723e82dc018c096f3) This has been failing when
DEBUG is #defined.

Signed-off-by: Tony Breeds 
Signed-off-by: Benjamin Herrenschmidt

powerpc+of: Add of node/property notification chain for adds and removes

2012-11-15T01:56:41+00:00

This patch moves the notification chain for updates to the device tree
from the powerpc/pseries code to the base OF code. This makes this
functionality available to all architectures.

Additionally the notification chain is updated to allow notifications
for property add/remove/update. To make this work a pointer to a new
struct (of_prop_reconfig) is passed to the routines in the notification chain.
The of_prop_reconfig property contains a pointer to the node containing the
property and a pointer to the property itself. In the case of property
updates, the property pointer refers to the new property.

Signed-off-by: Nathan Fontenot 
Acked-by: Rob Herring 
Acked-by: Grant Likely 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Change memory_limit from phys_addr_t to unsigned long long

2012-09-07T01:44:30+00:00

There are some device-tree nodes, whose values are of type phys_addr_t.
The phys_addr_t is variable sized based on the CONFIG_PHSY_T_64BIT.

Change these to a fixed unsigned long long for consistency.

This patch does the change only for memory_limit.

The following is a list of such variables which need the change:

 1) kernel_end, crashk_size - in arch/powerpc/kernel/machine_kexec.c

 2) (struct resource *)crashk_res.start - We could export a local static
    variable from machine_kexec.c.

Changing the above values might break the kexec-tools. So, I will
fix kexec-tools first to handle the different sized values and then change
 the above.

Suggested-by: Benjamin Herrenschmidt 
Signed-off-by: Suzuki K. Poulose 
Signed-off-by: Benjamin Herrenschmidt

Disintegrate asm/system.h for PowerPC

2012-03-28T17:30:02+00:00

Disintegrate asm/system.h for PowerPC.

Signed-off-by: David Howells 
Acked-by: Benjamin Herrenschmidt 
cc: linuxppc-dev@lists.ozlabs.org

fadump: Remove the phyp assisted dump code.

2012-02-22T23:50:03+00:00

Remove the phyp assisted dump implementation which is not is use.

Signed-off-by: Mahesh Salgaonkar 
Signed-off-by: Benjamin Herrenschmidt

fadump: Reserve the memory for firmware assisted dump.

2012-02-22T23:50:01+00:00

Reserve the memory during early boot to preserve CPU state data, HPTE region
and RMA (real mode area) region data in case of kernel crash. At the time of
crash, powerpc firmware will store CPU state data, HPTE region data and move
RMA region data to the reserved memory area.

If the firmware-assisted dump fails to reserve the memory, then fallback
to existing kexec-based kdump.

Most of the code implementation to reserve memory has been
adapted from phyp assisted dump implementation written by Linas Vepstas
and Manish Ahuja

This patch also introduces a config option CONFIG_FA_DUMP for firmware
assisted dump feature on Powerpc (ppc64) architecture.

Signed-off-by: Mahesh Salgaonkar 
Signed-off-by: Benjamin Herrenschmidt

memblock: s/memblock_analyze()/memblock_allow_resize()/ and update users

2011-12-08T18:22:08+00:00

The only function of memblock_analyze() is now allowing resize of
memblock region arrays.  Rename it to memblock_allow_resize() and
update its users.

* The following users remain the same other than renaming.

  arm/mm/init.c::arm_memblock_init()
  microblaze/kernel/prom.c::early_init_devtree()
  powerpc/kernel/prom.c::early_init_devtree()
  openrisc/kernel/prom.c::early_init_devtree()
  sh/mm/init.c::paging_init()
  sparc/mm/init_64.c::paging_init()
  unicore32/mm/init.c::uc32_memblock_init()

* In the following users, analyze was used to update total size which
  is no longer necessary.

  powerpc/kernel/machine_kexec.c::reserve_crashkernel()
  powerpc/kernel/prom.c::early_init_devtree()
  powerpc/mm/init_32.c::MMU_init()
  powerpc/mm/tlb_nohash.c::__early_init_mmu()  
  powerpc/platforms/ps3/mm.c::ps3_mm_add_memory()
  powerpc/platforms/embedded6xx/wii.c::wii_memory_fixups()
  sh/kernel/machine_kexec.c::reserve_crashkernel()

* x86/kernel/e820.c::memblock_x86_fill() was directly setting
  memblock_can_resize before populating memblock and calling analyze
  afterwards.  Call memblock_allow_resize() before start populating.

memblock_can_resize is now static inside memblock.c.

Signed-off-by: Tejun Heo 
Cc: Benjamin Herrenschmidt 
Cc: Yinghai Lu 
Cc: Russell King 
Cc: Michal Simek 
Cc: Paul Mundt 
Cc: "David S. Miller" 
Cc: Guan Xuetao 
Cc: "H. Peter Anvin"

powerpc: Cleanup memblock usage

2011-12-08T18:22:07+00:00

* early_init_devtree(): Total memory size is aligned to PAGE_SIZE;
  however, alignment isn't enforced if memory_limit is explicitly
  specified.  Simplify the logic and always apply PAGE_SIZE alignment.

* MMU_init(): memblock regions is truncated by directly modifying
  memblock.memory.cnt.  This is incomplete (reserved array is not
  truncated) and unnecessarily low level hindering further memblock
  improvments.  Use memblock_enforce_memory_limit() instead.

* wii_memory_fixups(): Unnecessarily low level direct manipulation of
  memblock regions.  The same result can be achieved using properly
  abstracted operations.  Reimplement using memblock API.

Signed-off-by: Tejun Heo 
Cc: Benjamin Herrenschmidt 
Cc: Yinghai Lu