<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/powerpc/kernel/prom.c, branch v4.18</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>powerpc/prom: Drop support for old FDT versions</title>
<updated>2018-05-11T13:29:04+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2018-05-09T13:42:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=89c190627257a38d5e4d7cb3e5382f0e6e089f7c'/>
<id>89c190627257a38d5e4d7cb3e5382f0e6e089f7c</id>
<content type='text'>
In commit e6a6928c3ea1 ("of/fdt: Convert FDT functions to use
libfdt") (Apr 2014), the generic flat device tree code dropped support
for flat device tree's older than version 0x10 (16).

We still have code in our CPU scanning to cope with flat device tree
versions earlier than 2, which can now never trigger, so drop it.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In commit e6a6928c3ea1 ("of/fdt: Convert FDT functions to use
libfdt") (Apr 2014), the generic flat device tree code dropped support
for flat device tree's older than version 0x10 (16).

We still have code in our CPU scanning to cope with flat device tree
versions earlier than 2, which can now never trigger, so drop it.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'topic/paca' into next</title>
<updated>2018-03-30T22:09:36+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2018-03-30T13:11:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f437c51748fa1dd423a878c870ad203843a51c8d'/>
<id>f437c51748fa1dd423a878c870ad203843a51c8d</id>
<content type='text'>
Bring in yet another series that touches KVM code, and might need to
be merged into the kvm-ppc branch to resolve conflicts.

This required some changes in pnv_power9_force_smt4_catch/release()
due to the paca array becomming an array of pointers.
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Bring in yet another series that touches KVM code, and might need to
be merged into the kvm-ppc branch to resolve conflicts.

This required some changes in pnv_power9_force_smt4_catch/release()
due to the paca array becomming an array of pointers.
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64: Defer paca allocation until memory topology is discovered</title>
<updated>2018-03-30T12:34:28+00:00</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2018-02-13T15:08:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=59f577743d71bf796ceac10961bf6cfa5ca26786'/>
<id>59f577743d71bf796ceac10961bf6cfa5ca26786</id>
<content type='text'>
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
[mpe: Rename the dummy allocate_pacas() to fix 32-bit build]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
[mpe: Rename the dummy allocate_pacas() to fix 32-bit build]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/setup: Add cpu_to_phys_id array</title>
<updated>2018-03-30T12:34:27+00:00</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2018-02-13T15:08:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9f593f131ed463dc571290980dd12cb9e56d8ea5'/>
<id>9f593f131ed463dc571290980dd12cb9e56d8ea5</id>
<content type='text'>
Build an array that finds hardware CPU number from logical CPU
number in firmware CPU discovery. Use that rather than setting
paca of other CPUs directly, to begin with. Subsequent patch will
not have pacas allocated at this point.

Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
[mpe: Fix SMP=n build by adding #ifdef in arch_match_cpu_phys_id()]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Build an array that finds hardware CPU number from logical CPU
number in firmware CPU discovery. Use that rather than setting
paca of other CPUs directly, to begin with. Subsequent patch will
not have pacas allocated at this point.

Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
[mpe: Fix SMP=n build by adding #ifdef in arch_match_cpu_phys_id()]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/prom: Remove warning on array size when empty</title>
<updated>2018-03-13T04:50:40+00:00</updated>
<author>
<name>Mathieu Malaterre</name>
<email>malat@debian.org</email>
</author>
<published>2018-03-02T19:49:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4f1f40f7b2b4487f582ecafec64076e430c72b22'/>
<id>4f1f40f7b2b4487f582ecafec64076e430c72b22</id>
<content type='text'>
When neither CONFIG_ALTIVEC, nor CONFIG_VSX or CONFIG_PPC64 is
defined, the array feature_properties is defined as an empty array,
which in turn triggers the following warning (treated as error on
W=1):

  arch/powerpc/kernel/prom.c: In function ‘check_cpu_feature_properties’:
  arch/powerpc/kernel/prom.c:298:16: error: comparison of unsigned expression &lt; 0 is always false
    for (i = 0; i &lt; ARRAY_SIZE(feature_properties); ++i, ++fp) {
                  ^

Suggested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Mathieu Malaterre &lt;malat@debian.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When neither CONFIG_ALTIVEC, nor CONFIG_VSX or CONFIG_PPC64 is
defined, the array feature_properties is defined as an empty array,
which in turn triggers the following warning (treated as error on
W=1):

  arch/powerpc/kernel/prom.c: In function ‘check_cpu_feature_properties’:
  arch/powerpc/kernel/prom.c:298:16: error: comparison of unsigned expression &lt; 0 is always false
    for (i = 0; i &lt; ARRAY_SIZE(feature_properties); ++i, ++fp) {
                  ^

Suggested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Mathieu Malaterre &lt;malat@debian.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/mm: Separate ibm, dynamic-memory data from DT format</title>
<updated>2018-01-16T12:26:27+00:00</updated>
<author>
<name>Nathan Fontenot</name>
<email>nfont@linux.vnet.ibm.com</email>
</author>
<published>2017-12-01T16:47:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6c6ea53725b357fa3deac96d8d2d4ee785b67c6b'/>
<id>6c6ea53725b357fa3deac96d8d2d4ee785b67c6b</id>
<content type='text'>
We currently have code to parse the dynamic reconfiguration LMB
information from the ibm,dynamic-meory device tree property in
multiple locations; numa.c, prom.c, and pseries/hotplug-memory.c.
In anticipation of adding support for a version 2 of the
ibm,dynamic-memory property this patch aims to separate the device
tree information from the device tree format.

Doing this requires a two step process to avoid a possibly very large
bootmem allocation early in boot. During initial boot, new routines
are provided to walk the device tree property and make a call-back
for each LMB.

The second step (introduced in later patches) will allocate an
array of LMB information that can be used directly without needing
to know the DT format.

This approach provides the benefit of consolidating the device tree
property parsing to a single location and (eventually) providing
a common data structure for retrieving LMB information.

This patch introduces a routine to walk the ibm,dynamic-memory
property in the flattened device tree and updates the prom.c code
to use this to initialize memory.

Signed-off-by: Nathan Fontenot &lt;nfont@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We currently have code to parse the dynamic reconfiguration LMB
information from the ibm,dynamic-meory device tree property in
multiple locations; numa.c, prom.c, and pseries/hotplug-memory.c.
In anticipation of adding support for a version 2 of the
ibm,dynamic-memory property this patch aims to separate the device
tree information from the device tree format.

Doing this requires a two step process to avoid a possibly very large
bootmem allocation early in boot. During initial boot, new routines
are provided to walk the device tree property and make a call-back
for each LMB.

The second step (introduced in later patches) will allocate an
array of LMB information that can be used directly without needing
to know the DT format.

This approach provides the benefit of consolidating the device tree
property parsing to a single location and (eventually) providing
a common data structure for retrieving LMB information.

This patch introduces a routine to walk the ibm,dynamic-memory
property in the flattened device tree and updates the prom.c code
to use this to initialize memory.

Signed-off-by: Nathan Fontenot &lt;nfont@linux.vnet.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64</title>
<updated>2017-11-06T05:48:14+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2017-10-19T04:08:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4e003747043d57aa75c9762fa148ef38afe68dd8'/>
<id>4e003747043d57aa75c9762fa148ef38afe68dd8</id>
<content type='text'>
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU
on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU
found in "server" processors, from IBM mainly.

Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's
annoying to have two symbols that always have the same value, it's not
quite annoying enough to bother removing one.

However with the arrival of Power9, we now have the situation where
CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the
Radix MMU - *not* the "standard" MMU. So it is now actively confusing
to use it, because it implies that code is disabled or inactive when
the Radix MMU is in use, however that is not necessarily true.

So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor
formatting updates of some of the affected lines.

This will be a pain for backports, but c'est la vie.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU
on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU
found in "server" processors, from IBM mainly.

Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's
annoying to have two symbols that always have the same value, it's not
quite annoying enough to bother removing one.

However with the arrival of Power9, we now have the situation where
CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the
Radix MMU - *not* the "standard" MMU. So it is now actively confusing
to use it, because it implies that code is disabled or inactive when
the Radix MMU is in use, however that is not necessarily true.

So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor
formatting updates of some of the affected lines.

This will be a pain for backports, but c'est la vie.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/powernv: Enable TM without suspend if possible</title>
<updated>2017-10-20T22:33:05+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2017-10-12T10:17:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=54820530c5faa9fd78e1c08cb6449100b1a19157'/>
<id>54820530c5faa9fd78e1c08cb6449100b1a19157</id>
<content type='text'>
Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.

We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.

We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/tm: Add commandline option to disable hardware transactional memory</title>
<updated>2017-10-20T00:10:56+00:00</updated>
<author>
<name>Cyril Bur</name>
<email>cyrilbur@gmail.com</email>
</author>
<published>2017-10-12T10:17:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=07fd1761e1cd2b5ecdb470fc228d52ccdf75e05b'/>
<id>07fd1761e1cd2b5ecdb470fc228d52ccdf75e05b</id>
<content type='text'>
Currently the kernel relies on firmware to inform it whether or not the
CPU supports HTM and as long as the kernel was built with
CONFIG_PPC_TRANSACTIONAL_MEM=y then it will allow userspace to make
use of the facility.

There may be situations where it would be advantageous for the kernel
to not allow userspace to use HTM, currently the only way to achieve
this is to recompile the kernel with CONFIG_PPC_TRANSACTIONAL_MEM=n.

This patch adds a simple commandline option so that HTM can be
disabled at boot time.

Signed-off-by: Cyril Bur &lt;cyrilbur@gmail.com&gt;
[mpe: Simplify to a bool, move to prom.c, put doco in the right place.
 Always disable, regardless of initial state, to avoid user confusion.]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently the kernel relies on firmware to inform it whether or not the
CPU supports HTM and as long as the kernel was built with
CONFIG_PPC_TRANSACTIONAL_MEM=y then it will allow userspace to make
use of the facility.

There may be situations where it would be advantageous for the kernel
to not allow userspace to use HTM, currently the only way to achieve
this is to recompile the kernel with CONFIG_PPC_TRANSACTIONAL_MEM=n.

This patch adds a simple commandline option so that HTM can be
disabled at boot time.

Signed-off-by: Cyril Bur &lt;cyrilbur@gmail.com&gt;
[mpe: Simplify to a bool, move to prom.c, put doco in the right place.
 Always disable, regardless of initial state, to avoid user confusion.]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Fix booting P9 hash with CONFIG_PPC_RADIX_MMU=N</title>
<updated>2017-05-25T13:07:44+00:00</updated>
<author>
<name>Michael Neuling</name>
<email>mikey@neuling.org</email>
</author>
<published>2017-05-24T07:03:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d957fb4d173647640a2b83e7c7e56a580e7fc7e7'/>
<id>d957fb4d173647640a2b83e7c7e56a580e7fc7e7</id>
<content type='text'>
Currently if you disable CONFIG_PPC_RADIX_MMU you'll crash on boot on
a P9. This is because we still set MMU_FTR_TYPE_RADIX via
ibm,pa-features and MMU_FTR_TYPE_RADIX is what's used for code patching
in much of the asm code (ie. slb_miss_realmode)

This patch fixes the problem by stopping MMU_FTR_TYPE_RADIX from being
set from ibm.pa-features.

We may eventually end up removing the CONFIG_PPC_RADIX_MMU option
completely but until then this fixes the issue.

Fixes: 17a3dd2f5fc7 ("powerpc/mm/radix: Use firmware feature to enable Radix MMU")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Michael Neuling &lt;mikey@neuling.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently if you disable CONFIG_PPC_RADIX_MMU you'll crash on boot on
a P9. This is because we still set MMU_FTR_TYPE_RADIX via
ibm,pa-features and MMU_FTR_TYPE_RADIX is what's used for code patching
in much of the asm code (ie. slb_miss_realmode)

This patch fixes the problem by stopping MMU_FTR_TYPE_RADIX from being
set from ibm.pa-features.

We may eventually end up removing the CONFIG_PPC_RADIX_MMU option
completely but until then this fixes the issue.

Fixes: 17a3dd2f5fc7 ("powerpc/mm/radix: Use firmware feature to enable Radix MMU")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Michael Neuling &lt;mikey@neuling.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
</feed>
