Commit Graph

51 Commits

Author SHA1 Message Date
David S. Miller
c73fcc846c [SPARC]: Fix serial console device detection.
The current scheme works on static interpretation of text names, which
is wrong.

The output-device setting, for example, must be resolved via an alias
or similar to a full path name to the console device.

Paths also contain an optional set of 'options', which starts with a
colon at the end of the path.  The option area is used to specify
which of two serial ports ('a' or 'b') the path refers to when a
device node drives multiple ports.  'a' is assumed if the option
specification is missing.

This was caught by the UltraSPARC-T1 simulator.  The 'output-device'
property was set to 'ttya' and we didn't pick upon the fact that this
is an OBP alias set to '/virtual-devices/console'.  Instead we saw it
as the first serial console device, instead of the hypervisor console.

The infrastructure is now there to take advantage of this to resolve
the console correctly even in multi-head situations in fbcon too.

Thanks to Greg Onufer for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-20 16:59:26 -07:00
Fabio Massimo Di Nitto
3ac66e33ea [SPARC64]: SMP build fix.
The UP build fix had some unintended consequences.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-16 17:11:58 -07:00
David S. Miller
d54bc2793e [SPARC64]: Fix UP build.
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-16 04:41:51 -07:00
David S. Miller
8b99cfb8cc [SPARC64]: More sensible udelay implementation.
Take a page from the powerpc folks and just calculate the
delay factor directly.

Since frequency scaling chips use a system-tick register,
the value is going to be the same system-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-16 04:05:02 -07:00
David S. Miller
eff3414b72 [SPARC64]: Move topology init code into new file, sysfs.c
Also, use per-cpu data for struct cpu.  Calling kmalloc for
each cpu in topology_init() is just plain clumsy.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-04 21:49:50 -07:00
David S. Miller
5cbc307373 [SPARC64]: Use machine description and OBP properly for cpu probing.
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-29 02:49:41 -07:00
David S. Miller
c7754d465b [SPARC64]: Add hypervisor API negotiation and fix console bugs.
Hypervisor interfaces need to be negotiated in order to use
some API calls reliably.  So add a small set of interfaces
to request API versions and query current settings.

This allows us to fix some bugs in the hypervisor console:

1) If we can negotiate API group CORE of at least major 1
   minor 1 we can use con_read and con_write which can improve
   console performance quite a bit.

2) When we do a console write request, we should hold the
   spinlock around the whole request, not a byte at a time.
   What would happen is that it's easy for output from
   different cpus to get mixed with each other.

3) Use consistent udelay() based polling, udelay(1) each
   loop with a limit of 1000 polls to handle stuck hypervisor
   console.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-15 20:23:02 -07:00
Alon Bar-Lev
383464c0fb [PATCH] Dynamic kernel command-line: sparc64
Rename saved_command_line into boot_command_line.

Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:39 -08:00
David S. Miller
7341df16a1 [SPARC]: Kill BOOTME_SINGLE.
Unused, but still allow the '-s' boot option to be passed
down to init.

Based upon patches by Martin Habets.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-17 19:28:49 -07:00
Martin Habets
eba8cefc78 [SPARC32]: Fix sparc32 modpost warnings with sunzilog
Fix this 2.6.19-rc1 build warnings from modpost:

WARNING: vmlinux - Section mismatch: reference to .init.text:sunzilog_console_setup from .data between 'sunzilog_console' (at offset 0x8394) and 'devices_subsys'

Signed-off-by: Martin Habets <errandir_news@mph.eclipse.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-11 23:56:53 -07:00
Jon Smirl
894673ee61 [PATCH] tty: Remove include of screen_info.h from tty.h
screen_info.h doesn't have anything to do with the tty layer and shouldn't be
included by tty.h.  This patches removes the include and modifies all users to
directly include screen_info.h.  struct screen_info is mainly used to
communicate with the console drivers in drivers/video/console.  Note that this
patch touches every arch and I have no way of testing it.  If there is a
mistake the worst thing that will happen is a compile error.

[akpm@osdl.org: fix arm build]
[akpm@osdl.org: fix alpha build]
Signed-off-by: Jon Smirl <jonsmir@gmail.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:16 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
KAMEZAWA Hiroyuki
76b67ed9dc [PATCH] node hotplug: register cpu: remove node struct
With Goto-san's patch, we can add new pgdat/node at runtime.  I'm now
considering node-hot-add with cpu + memory on ACPI.

I found acpi container, which describes node, could evaluate cpu before
memory. This means cpu-hot-add occurs before memory hot add.

In most part, cpu-hot-add doesn't depend on node hot add.  But register_cpu(),
which creates symbolic link from node to cpu, requires that node should be
onlined before register_cpu().  When a node is onlined, its pgdat should be
there.

This patch-set holds off creating symbolic link from node to cpu
until node is onlined.

This removes node arguments from register_cpu().

Now, register_cpu() requires 'struct node' as its argument.  But the array of
struct node is now unified in driver/base/node.c now (By Goto's node hotplug
patch).  We can get struct node in generic way.  So, this argument is not
necessary now.

This patch also guarantees add cpu under node only when node is onlined.  It
is necessary for node-hot-add vs.  cpu-hot-add patch following this.

Moreover, register_cpu calculates cpu->node_id by cpu_to_node() without regard
to its 'struct node *root' argument.  This patch removes it.

Also modify callers of register_cpu()/unregister_cpu, whose args are changed
by register-cpu-remove-node-struct patch.

[Brice.Goglin@ens-lyon.org: fix it]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:37 -07:00
David S. Miller
765b5f3273 [SPARC64]: Must run smp_setup_cpu_possible_map() after paging_init()
Otherwise the in-kernel PROM device tree isn't built yet,
and therefore the present cpu bits don't get set properly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23 23:15:23 -07:00
David S. Miller
951bc82c53 [SPARC64]: Make smp_processor_id() functional before start_kernel()
Uses of smp_processor_id() get pushed earlier and earlier in
the start_kernel() sequence.  So just get it working before
we call start_kernel() to avoid all possible problems.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-31 01:24:02 -07:00
KAMEZAWA Hiroyuki
a283a52520 [PATCH] for_each_possible_cpu: sparc64
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu.
for sparc64.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:31 -07:00
Andrew Morton
467418f350 [SPARC64]: CONFIG_BLK_DEV_RAM fix
init/do_mounts_rd.c depends upon CONFIG_BLK_DEV_RAM, not CONFIG_BLK_DEV_INITRD.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:16:41 -08:00
David S. Miller
90a6646bf6 [SPARC64]: Fix system type in /proc/cpuinfo and remove bogus OBP check.
Report 'sun4v' when appropriate in /proc/cpuinfo

Remove all the verifications of the OBP version string.  Just
make sure it's there, and report it raw in the bootup logs and
via /proc/cpuinfo.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:14:25 -08:00
Eric Sesterhenn
9132983ae1 [SPARC64]: kzalloc() conversion
this patch converts arch/sparc64 to kzalloc usage.
Crosscompile tested with allyesconfig.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:14:19 -08:00
David S. Miller
52845cdb3b [SPARC64]: Init boot cpu's trap_block[] before paging_init()
It must be ready when we take over the trap table.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:13:30 -08:00
David S. Miller
ebd8c56c5a [SPARC64]: Fix uniprocessor IRQ targetting on SUN4V.
We need to use the real hardware processor ID when
targetting interrupts, not the "define to 0" thing
the uniprocessor build gives us.

Also, fill in the Node-ID and Agent-ID fields properly
on sun4u/Safari.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:13:24 -08:00
David S. Miller
72aff53f1f [SPARC64]: Get SUN4V SMP working.
The sibling cpu bringup is extremely fragile.  We can only
perform the most basic calls until we take over the trap
table from the firmware/hypervisor on the new cpu.

This means no accesses to %g4, %g5, %g6 since those can't be
TLB translated without our trap handlers.

In order to achieve this:

1) Change sun4v_init_mondo_queues() so that it can operate in
   several modes.

   It can allocate the queues, or install them in the current
   processor, or both.

   The boot cpu does both in it's call early on.

   Later, the boot cpu allocates the sibling cpu queue, starts
   the sibling cpu, then the sibling cpu loads them in.

2) init_cur_cpu_trap() is changed to take the current_thread_info()
   as an argument instead of reading %g6 directly on the current
   cpu.

3) Create a trampoline stack for the sibling cpus.  We do our basic
   kernel calls using this stack, which is locked into the kernel
   image, then go to our proper thread stack after taking over the
   trap table.

4) While we are in this delicate startup state, we put 0xdeadbeef
   into %g4/%g5/%g6 in order to catch accidental accesses.

5) On the final prom_set_trap_table*() call, we put &init_thread_union
   into %g6.  This is a hack to make prom_world(0) work.  All that
   wants to do is restore the %asi register using
   get_thread_current_ds().

Longer term we should just do the OBP calls to set the trap table by
hand just like we do for everything else.  This would avoid that silly
prom_world(0) issue, then we can remove the init_thread_union hack.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:13:22 -08:00
David S. Miller
d5a2aa241a [SPARC64] sunhv: Bug fixes.
Add udelay to polling console write loop, and increment
the loop limit.

Name the device "ttyHV" and pass that to add_preferred_console()
when we're using hypervisor console.

Kill sunhv_console_setup(), it's empty.

Handle the case where we don't want to use hypervisor console.
(ie. we have a head attached to a sun4v machine)

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:46 -08:00
David S. Miller
1a7a242c89 [SPARC64]: Recognize "virtual-console" as input and output console device.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:28 -08:00
David S. Miller
c4bce90ea2 [SPARC64]: Deal with PTE layout differences in SUN4V.
Yes, you heard it right, they changed the PTE layout for
SUN4V.  Ho hum...

This is the simple and inefficient way to support this.
It'll get optimized, don't worry.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:25 -08:00
David S. Miller
fd05068d7b [SPARC64]: Fix typo in sun4v_patch().
Second instruction offset is '4' not '3'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:22 -08:00
David S. Miller
3a8c069d0e [SPARC64]: Print ARCH as SUN4V when tlb_type is hypervisor.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:04 -08:00
David S. Miller
d82ace7dc4 [SPARC64]: Detect sun4v early in boot process.
We look for "SUNW,sun4v" in the 'compatible' property
of the root OBP device tree node.

Protect every %ver register access, to make sure it is
not touched on sun4v, as %ver is hyperprivileged there.

Lock kernel TLB entries using hypervisor calls instead of
calls into OBP.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:03 -08:00
David S. Miller
8b11bd12af [SPARC64]: Patch up mmu context register writes for sun4v.
sun4v uses ASI_MMU instead of ASI_DMMU

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:56 -08:00
David S. Miller
df7d6aec96 [SPARC64]: Rename gl_{1,2}insn_patch --> sun4v_{1,2}insn_patch
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:53 -08:00
David S. Miller
840aaef8db [SPARC64]: Add missing memory barriers to instruction patching functions.
V9 requires a write memory barrier before the instruction flush.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:51 -08:00
David S. Miller
45fec05f80 [SPARC64]: Sanitize %pstate writes for sun4v.
If we're just switching between different alternate global
sets, nop it out on sun4v.  Also, get rid of all of the
alternate global save/restore in the OBP CIF trampoline code.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:50 -08:00
David S. Miller
936f482af1 [SPARC64]: Add initial code to twiddle %gl on trap entry/exit.
Instead of setting/clearing PSTATE_AG we have to change
the %gl register value on sun4v.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:48 -08:00
David S. Miller
d96b81533b [SPARC64]: Add sun4v case to __GET_CPUID() patch tables.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:45 -08:00
David S. Miller
92704a1c63 [SPARC64]: Refine code sequences to get the cpu id.
On uniprocessor, it's always zero for optimize that.

On SMP, the jmpl to the stub kills the return address stack in the cpu
branch prediction logic, so expand the code sequence inline and use a
code patching section to fix things up.  This also always better and
explicit register selection, which will be taken advantage of in a
future changeset.

The hard_smp_processor_id() function is big, so do not inline it.

Fix up tests for Jalapeno to also test for Serrano chips too.  These
tests want "jbus Ultra-IIIi" cases to match, so that is what we should
test for.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:35 -08:00
David S. Miller
56fb4df6da [SPARC64]: Elminate all usage of hard-coded trap globals.
UltraSPARC has special sets of global registers which are switched to
for certain trap types.  There is one set for MMU related traps, one
set of Interrupt Vector processing, and another set (called the
Alternate globals) for all other trap types.

For what seems like forever we've hard coded the values in some of
these trap registers.  Some examples include:

1) Interrupt Vector global %g6 holds current processors interrupt
   work struct where received interrupts are managed for IRQ handler
   dispatch.

2) MMU global %g7 holds the base of the page tables of the currently
   active address space.

3) Alternate global %g6 held the current_thread_info() value.

Such hardcoding has resulted in some serious issues in many areas.
There are some code sequences where having another register available
would help clean up the implementation.  Taking traps such as
cross-calls from the OBP firmware requires some trick code sequences
wherein we have to save away and restore all of the special sets of
global registers when we enter/exit OBP.

We were also using the IMMU TSB register on SMP to hold the per-cpu
area base address, which doesn't work any longer now that we actually
use the TSB facility of the cpu.

The implementation is pretty straight forward.  One tricky bit is
getting the current processor ID as that is different on different cpu
variants.  We use a stub with a fancy calling convention which we
patch at boot time.  The calling convention is that the stub is
branched to and the (PC - 4) to return to is in register %g1.  The cpu
number is left in %g6.  This stub can be invoked by using the
__GET_CPUID macro.

We use an array of per-cpu trap state to store the current thread and
physical address of the current address space's page tables.  The
TRAP_LOAD_THREAD_REG loads %g6 with the current thread from this
table, it uses __GET_CPUID and also clobbers %g1.

TRAP_LOAD_IRQ_WORK is used by the interrupt vector processing to load
the current processor's IRQ software state into %g6.  It also uses
__GET_CPUID and clobbers %g1.

Finally, TRAP_LOAD_PGD_PHYS loads the physical address base of the
current address space's page tables into %g7, it clobbers %g1 and uses
__GET_CPUID.

Many refinements are possible, as well as some tuning, with this stuff
in place.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:11:16 -08:00
David S. Miller
7abea92145 [SPARC64]: Make cpu_present_map available earlier.
The change to kernel/sched.c's init code to use for_each_cpu()
requires that the cpu_possible_map be setup much earlier.

Set it up via setup_arch(), constrained to NR_CPUS, and later
constrain it to max_cpus in smp_prepare_cpus().

This fixes SMP booting on sparc64.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-26 19:36:00 -08:00
Eddie C. Dost
c126cf80d4 [SPARC64]: Serial Console for E250 Patch
From: Eddie C. Dost <ecd@brainaid.de>

I have the following patch for serial console over the RSC
(remote system controller) on my E250 machine. It basically adds
support for input-device=rsc and output-device=rsc from OBP, and
allows 115200,8,n,1,- serial mode setting.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-18 14:54:31 -08:00
Al Viro
f3169641c1 [PATCH] sparc64: task_thread_info()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:52 -08:00
David S. Miller
4d45cbacb8 [SPARC64]: Restore 2.4.x /proc/cpuinfo behavior for "ncpus probed" field.
Noticed by Tom 'spot' Callaway.

Even on uniprocessor we always reported the number of physical
cpus in the system via /proc/cpuinfo.  But when this got changed
to use num_possible_cpus() it always reads as "1" on uniprocessor.
This change was unintentional.

So scan the firmware device tree and count the number of cpu
nodes, and report that, as we always did.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-11 12:48:56 -08:00
Hugh Dickins
b8ae48656d [SPARC64] mm: don't re-evaluate *ptep
sparc64 prom_callback and new_setup_frame32 each operates on a user page
table without holding lock, and no doubt they've good reason.  But I'd
feel more confident if they were to do a "pte = *ptep" and then operate
on pte, rather than re-evaluating *ptep.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-07 14:08:46 -08:00
David S. Miller
0835ae0f27 [SPARC64]: Replace cheetah+ code patching with variables.
Instead of code patching to handle the page size fields in
the context registers, just use variables from which we get
the proper values.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-04 15:23:20 -07:00
David S. Miller
0836a0eb40 [SPARC64]: Move phys_base, kern_{base,size}, and sp_banks[] init to paging_init
Also, move prom_probe_memory() into arch/sparc64/mm/init.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 21:38:08 -07:00
David S. Miller
801ab3c731 [SPARC]: Declare paging_init() in asm/pgtable.h
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 21:31:25 -07:00
David S. Miller
80dc0d6b44 [SPARC64]: Probe D/I/E-cache config and use.
At boot time, determine the D-cache, I-cache and E-cache size and
line-size.  Use them in cache flushes when appropriate.

This change was motivated by discovering that the D-cache on
UltraSparc-IIIi and later are 64K not 32K, and the flushes done by the
Cheetah error handlers were assuming a 32K size.

There are still some pieces of code that are hard coding things and
will need to be fixed up at some point.

While we're here, fix the D-cache and I-cache parity error handlers
to run with interrupts disabled, and when the trap occurs at trap
level > 1 log the event via a counter displayed in /proc/cpuinfo.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-26 00:32:17 -07:00
David S. Miller
1c9ea5db00 [SPARC64]: Kill unused variable in setup_arch()
'highest_paddr' is set, but never actually used.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-23 11:54:43 -07:00
David S. Miller
bff06d5522 [SPARC64]: Rewrite bootup sequence.
Instead of all of this cpu-specific code to remap the kernel
to the correct location, use portable firmware calls to do
this instead.

What we do now is the following in position independant
assembler:

	chosen_node = prom_finddevice("/chosen");
	prom_mmu_ihandle_cache = prom_getint(chosen_node, "mmu");
	vaddr = 4MB_ALIGN(current_text_addr());
	prom_translate(vaddr, &paddr_high, &paddr_low, &mode);
	prom_boot_mapping_mode = mode;
	prom_boot_mapping_phys_high = paddr_high;
	prom_boot_mapping_phys_low = paddr_low;
	prom_map(-1, 8 * 1024 * 1024, KERNBASE, paddr_low);

and that replaces the massive amount of by-hand TLB probing and
programming we used to do here.

The new code should also handle properly the case where the kernel
is mapped at the correct address already (think: future kexec
support).

Consequently, the bulk of remap_kernel() dies as does the entirety
of arch/sparc64/prom/map.S

We try to share some strings in the PROM library with the ones used
at bootup, and while we're here mark input strings to oplib.h routines
with "const" when appropriate.

There are many more simplifications now possible.  For one thing, we
can consolidate the two copies we now have of a lot of cpu setup code
sitting in head.S and trampoline.S.

This is a significant step towards CONFIG_DEBUG_PAGEALLOC support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 20:11:33 -07:00
David S. Miller
d7ce78fd9a [SPARC64]: Eliminate irq_cpustat_t.
We can put the __softirq_pending mask in the cpudata,
no need for the silly NR_CPUS array in kernel/softirq.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 22:46:43 -07:00
Kumar Gala
3d6364abcf [SPARC64]: remove use of asm/segment.h
Removed sparc64 architecture specific users of asm/segment.h and
asm-sparc64/segment.h itself

Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 12:45:30 -07:00
David S. Miller
816242da37 [SPARC64]: Add boot option to force UltraSPARC-III P-Cache on.
Older UltraSPARC-III chips have a P-Cache bug that makes us disable it
by default at boot time.

However, this does hurt performance substantially, particularly with
memcpy(), and the bug is _incredibly_ obscure.  I have never seen it
triggered in practice, ever.

So provide a "-P" boot option that forces the P-Cache on.  It taints
the kernel, so if it does trigger and cause some data corruption or
OOPS, we will find out in the logs that this option was on when it
happened.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-23 15:52:08 -07:00