Commit Graph

412728 Commits

Author SHA1 Message Date
Scott Wood
28efc35fe6 powerpc/e6500: TLB miss handler with hardware tablewalk support
There are a few things that make the existing hw tablewalk handlers
unsuitable for e6500:

 - Indirect entries go in TLB1 (though the resulting direct entries go in
   TLB0).

 - It has threads, but no "tlbsrx." -- so we need a spinlock and
   a normal "tlbsx".  Because we need this lock, hardware tablewalk
   is mandatory on e6500 unless we want to add spinlock+tlbsx to
   the normal bolted TLB miss handler.

 - TLB1 has no HES (nor next-victim hint) so we need software round robin
   (TODO: integrate this round robin data with hugetlb/KVM)

 - The existing tablewalk handlers map half of a page table at a time,
   because IBM hardware has a fixed 1MiB indirect page size.  e6500
   has variable size indirect entries, with a minimum of 2MiB.
   So we can't do the half-page indirect mapping, and even if we
   could it would be less efficient than mapping the full page.

 - Like on e5500, the linear mapping is bolted, so we don't need the
   overhead of supporting nested tlb misses.

Note that hardware tablewalk does not work in rev1 of e6500.
We do not expect to support e6500 rev1 in mainline Linux.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
2014-01-09 17:52:19 -06:00
Scott Wood
47ce8af420 powerpc: add barrier after writing kernel PTE
There is no barrier between something like ioremap() writing to
a PTE, and returning the value to a caller that may then store the
pointer in a place that is visible to other CPUs.  Such callers
generally don't perform barriers of their own.

Even if callers of ioremap() and similar things did use barriers,
the most logical choise would be smp_wmb(), which is not
architecturally sufficient when BookE hardware tablewalk is used.  A
full sync is specified by the architecture.

For userspace mappings, OTOH, we generally already have an lwsync due
to locking, and if we occasionally take a spurious fault due to not
having a full sync with hardware tablewalk, it will not be fatal
because we will retry rather than oops.

Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:19 -06:00
Kevin Hao
dde7dd3d67 powerpc/fsl_booke: enable the relocatable for the kdump kernel
The RELOCATABLE is more flexible and without any alignment restriction.
And it is a superset of DYNAMIC_MEMSTART. So use it by default for
a kdump kernel.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:18 -06:00
Kevin Hao
0be7d969b0 powerpc/fsl_booke: smp support for booting a relocatable kernel above 64M
When booting above the 64M for a secondary cpu, we also face the
same issue as the boot cpu that the PAGE_OFFSET map two different
physical address for the init tlb and the final map. So we have to use
switch_to_as1/restore_to_as0 between the conversion of these two
maps. When restoring to as0 for a secondary cpu, we only need to
return to the caller. So add a new parameter for function
restore_to_as0 for this purpose.

Use LOAD_REG_ADDR_PIC to get the address of variables which may
be used before we set the final map in cams for the secondary cpu.
Move the setting of cams a bit earlier in order to avoid the
unnecessary using of LOAD_REG_ADDR_PIC.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:18 -06:00
Kevin Hao
7d2471f9fa powerpc/fsl_booke: make sure PAGE_OFFSET map to memstart_addr for relocatable kernel
This is always true for a non-relocatable kernel. Otherwise the kernel
would get stuck. But for a relocatable kernel, it seems a little
complicated. When booting a relocatable kernel, we just align the
kernel start addr to 64M and map the PAGE_OFFSET from there. The
relocation will base on this virtual address. But if this address
is not the same as the memstart_addr, we will have to change the
map of PAGE_OFFSET to the real memstart_addr and do another relocation
again.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
[scottwood@freescale.com: make offset long and non-negative in simple case]
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:17 -06:00
Kevin Hao
813125d833 powerpc/fsl_booke: introduce map_mem_in_cams_addr
Introduce this function so we can set both the physical and virtual
address for the map in cams. This will be used by the relocation code.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:17 -06:00
Kevin Hao
b27652dd21 powerpc: introduce early_get_first_memblock_info
For a relocatable kernel since it can be loaded at any place, there
is no any relation between the kernel start addr and the memstart_addr.
So we can't calculate the memstart_addr from kernel start addr. And
also we can't wait to do the relocation after we get the real
memstart_addr from device tree because it is so late. So introduce
a new function we can use to get the first memblock address and size
in a very early stage (before machine_init).

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:17 -06:00
Kevin Hao
78a235efdc powerpc/fsl_booke: set the tlb entry for the kernel address in AS1
We use the tlb1 entries to map low mem to the kernel space. In the
current code, it assumes that the first tlb entry would cover the
kernel image. But this is not true for some special cases, such as
when we run a relocatable kernel above the 64M or set
CONFIG_KERNEL_START above 64M. So we choose to switch to address
space 1 before setting these tlb entries.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:16 -06:00
Kevin Hao
dd189692d4 powerpc: enable the relocatable support for the fsl booke 32bit kernel
This is based on the codes in the head_44x.S. The difference is that
the init tlb size we used is 64M. With this patch we can only load the
kernel at address between memstart_addr ~ memstart_addr + 64M. We will
fix this restriction in the following patches.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:16 -06:00
Kevin Hao
1c49abec67 powerpc: introduce macro LOAD_REG_ADDR_PIC
This is used to get the address of a variable when the kernel is not
running at the linked or relocated address.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:15 -06:00
Kevin Hao
99739611e8 powerpc/fsl_booke: introduce get_phys_addr function
Move the codes which translate a effective address to physical address
to a separate function. So it can be reused by other code.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:15 -06:00
Kevin Hao
7c732cba3d powerpc/fsl_booke: protect the access to MAS7
The e500v1 doesn't implement the MAS7, so we should avoid to access
this register on that implementations. In the current kernel, the
access to MAS7 are protected by either CONFIG_PHYS_64BIT or
MMU_FTR_BIG_PHYS. Since some code are executed before the code
patching, we have to use CONFIG_PHYS_64BIT in these cases.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:14 -06:00
Wang Dongsheng
d2dc13b533 powerpc/mpic_timer: fix convert ticks to time subtraction overflow
In some cases tmp_sec may be greater than ticks, because in the process
of calculation ticks and tmp_sec will be rounded.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:14 -06:00
Wang Dongsheng
0fd79588f9 powerpc/mpic_timer: fix the time is not accurate caused by GTCRR toggle bit
When the timer GTCCR toggle bit is inverted, we calculated the rest
of the time is not accurate. So we need to ignore this bit.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:13 -06:00
Wang Dongsheng
7f83a50ce3 powerpc/p1022ds: add a interrupt for rtc node
Add an external interrupt for rtc node.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:13 -06:00
Wang Dongsheng
1e7bf895cc powerpc/p1022ds: fix rtc compatible string
RTC Hardware(ds3232) and rtc compatible string does not match.
Change "dallas,ds1339" to "dallas,ds3232".

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:13 -06:00
Anton Blanchard
a183d3ae63 drivers/tty: ehv_bytechan fails to build as a module
ehv_bytechan is marked tristate but fails to build as a module:

drivers/tty/ehv_bytechan.c:363:1: error: type defaults to ‘int’ in declaration of ‘console_initcall’ [-Werror=implicit-int]

It doesn't make much sense for a console driver to be built as
a module, so change it to a bool.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:52:12 -06:00
Wang Dongsheng
a7189483f0 powerpc/85xx: add sysfs for pw20 state and altivec idle
Add a sys interface to enable/diable pw20 state or altivec idle, and
control the wait entry time.

Enable/Disable interface:
    0, disable. 1, enable.
    /sys/devices/system/cpu/cpuX/pw20_state
    /sys/devices/system/cpu/cpuX/altivec_idle

Set wait time interface:(Nanosecond)
    /sys/devices/system/cpu/cpuX/pw20_wait_time
    /sys/devices/system/cpu/cpuX/altivec_idle_wait_time
Example: Base on TBfreq is 41MHZ.
    1~48(ns): TB[63]
    49~97(ns): TB[62]
    98~195(ns): TB[61]
    196~390(ns): TB[60]
    391~780(ns): TB[59]
    781~1560(ns): TB[58]
    ...

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
[scottwood@freescale.com: change ifdef]
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-09 17:51:38 -06:00
Wang Dongsheng
1d47ddf7c3 powerpc/85xx: add hardware automatically enter pw20 state
Using hardware features make core automatically enter PW20 state.
Set a TB count to hardware, the effective count begins when PW10
is entered. When the effective period has expired, the core will
proceed from PW10 to PW20 if no exit conditions have occurred during
the period.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:40:28 -06:00
Wang Dongsheng
202e059ce3 powerpc/85xx: add hardware automatically enter altivec idle state
Each core's AltiVec unit may be placed into a power savings mode
by turning off power to the unit. Core hardware will automatically
power down the AltiVec unit after no AltiVec instructions have
executed in N cycles. The AltiVec power-control is triggered by hardware.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:39:48 -06:00
Wang Dongsheng
71a6fa17e1 powerpc/fsl: add E6500 PVR and SPRN_PWRMGTCR0 define
E6500 PVR and SPRN_PWRMGTCR0 will be used in subsequent pw20/altivec
idle patches.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:29:23 -06:00
Christian Engelmayer
1e83bf875e powerpc/sysdev: Fix a pci section mismatch for Book E
Moved the following functions out of the __init section:

   arch/powerpc/sysdev/fsl_pci.c      : fsl_add_bridge()
   arch/powerpc/sysdev/indirect_pci.c : setup_indirect_pci()

Those are referenced by arch/powerpc/sysdev/fsl_pci.c : fsl_pci_probe() when
compiling for Book E support.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:23:31 -06:00
Zhao Qiang
8b52312880 powerpc/p1010rdb-pa: modify phy interrupt.
It is not correct according to p1010rdb-pa user guide.
So modify it.

Signed-off-by: Zhao Qiang <B45475@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:15:12 -06:00
LEROY Christophe
189046981b powerpc 8xx: defconfig: slice by 4 is more efficient than the default slice by 8 on Powerpc 8xx.
On PPC_8xx, CRC32_SLICEBY4 is more efficient (almost twice) than CRC32_SLICEBY8,
as shown below:

With CRC32_SLICEBY8:
[    1.109204] crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64
[    1.114401] crc32: self tests passed, processed 225944 bytes in 15118910 nsec
[    1.130655] crc32c: CRC_LE_BITS = 64
[    1.134235] crc32c: self tests passed, processed 225944 bytes in 4479879 nsec

With CRC32_SLICEBY4:
[    1.097129] crc32: CRC_LE_BITS = 32, CRC_BE BITS = 32
[    1.101878] crc32: self tests passed, processed 225944 bytes in 8616242 nsec
[    1.116298] crc32c: CRC_LE_BITS = 32
[    1.119607] crc32c: self tests passed, processed 225944 bytes in 3289576 nsec

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:11:20 -06:00
Xie Xiaobo
8a6be2bdb6 powerpc/85xx: Add TWR-P1025 board support
TWR-P1025 Overview
 -----------------
 512Mbyte DDR3 (on board DDR)
 64MB Nor Flash
 eTSEC1: Connected to RGMII PHY AR8035
 eTSEC3: Connected to RGMII PHY AR8035
 Two USB2.0 Type A
 One microSD Card slot
 One mini-PCIe slot
 One mini-USB TypeB dual UART

Signed-off-by: Michael Johnston <michael.johnston@freescale.com>
Signed-off-by: Xie Xiaobo <X.Xie@freescale.com>
[scottwood@freescale.com: use pr_info rather than KERN_INFO]
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:09:29 -06:00
Xie Xiaobo
72c916ae97 powerpc/85xx: Add QE common init function
Define a QE init function in common file, and avoid
the same codes being duplicated in board files.

Signed-off-by: Xie Xiaobo <X.Xie@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:08:53 -06:00
Lijun Pan
3d73eb69fb powerpc/85xx: Merge 85xx/p1023_defconfig into mpc85xx_smp and mpc85xx
mpc85xx_smp_defconfig and mpc85xx_defconfig already have CONFIG_P1023RDS=y.
Merge CONFIG_P1023RDB=y and other relevant configurations into
mpc85xx_smp_defconfig and mpc85_defconfig.

Signed-off-by: Lijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:06:04 -06:00
Scott Wood
b58a7bd6df powerpc/fsl-booke: Use SPRN_SPRGn rather than mfsprg/mtsprg
This fixes a build break that was probably introduced with the removal
of -Wa,-me500 (commit f49596a4cf), where
the assembler refuses to recognize SPRG4-7 with a generic PPC target.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Dongsheng Wang <dongsheng.wang@freescale.com>
Cc: Anton Vorontsov <avorontsov@mvista.com>
Reviewed-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Tested-by: Wang Dongsheng <dongsheng.wang@freescale.com>
2014-01-07 19:06:03 -06:00
Kevin Hao
455d23a890 powerpc/85xx: don't init the mpic ipi for the SoC which has doorbell support
It makes no sense to initialize the mpic ipi for the SoC which has
doorbell support. So set the smp_85xx_ops.probe to NULL for this
case. Since the smp_85xx_ops.probe is also used in function
smp_85xx_setup_cpu() to check if we need to invoke
mpic_setup_this_cpu(), we introduce a new setup_cpu function
smp_85xx_basic_setup() to remove this dependency.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:06:03 -06:00
Zhao Qiang
0ff649ca50 powerpc/p1010rdb:update mtd of nand to adapt to both old and new p1010rdb
P1010rdb-pa and p1010rdb-pb have different mtd of nand.
So update dts to adapt to both p1010rdb-pa and p1010rdb-pb.

Move the nand-mtd from p1010rdb.dtsi to p1010rdb-pa*.dts.
Remove nand-mtd for p1010rdb-pb, whick will use mtdparts
from u-boot instead of nand-mtd in device tree.

Signed-off-by: Zhao Qiang <B45475@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:06:02 -06:00
Zhao Qiang
9667a36486 powerpc/p1010rdb:update dts to adapt to both old and new p1010rdb
P1010rdb-pa and p1010rdb-pb have different phy interrupts.
So update dts to adapt to both p1010rdb-pa and p1010rdb-pb.

Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Zhao Qiang <B45475@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 19:06:02 -06:00
Joseph Myers
01c9ccee3c powerpc: fix e500 SPE float SIGFPE generation
The e500 SPE floating-point emulation code is called from
SPEFloatingPointException and SPEFloatingPointRoundException in
arch/powerpc/kernel/traps.c.  Those functions have support for
generating SIGFPE, but do_spe_mathemu and speround_handler don't
generate a return value to indicate that this should be done.  Such a
return value should depend on whether an exception is raised that has
been set via prctl to generate SIGFPE.  This patch adds the relevant
logic in these functions so that SIGFPE is generated as expected by
the glibc testsuite.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:43:42 -06:00
Joseph Myers
28fbf1d540 powerpc: fix e500 SPE float to integer and fixed-point conversions
The e500 SPE floating-point emulation code has several problems in how
it handles conversions to integer and fixed-point fractional types.

There are the following 20 relevant instructions.  These can convert
to signed or unsigned 32-bit integers, either rounding towards zero
(as correct for C casts from floating-point to integer) or according
to the current rounding mode, or to signed or unsigned 32-bit
fixed-point values (values in the range [-1, 1) or [0, 1)).  For
conversion from double precision there are also instructions to
convert to 64-bit integers, rounding towards zero, although as far as
I know those instructions are completely theoretical (they are only
defined for implementations that support both SPE and classic 64-bit,
and I'm not aware of any such hardware even though the architecture
definition permits that combination).

#define EFSCTUI		0x2d4
#define EFSCTSI		0x2d5
#define EFSCTUF		0x2d6
#define EFSCTSF		0x2d7
#define EFSCTUIZ	0x2d8
#define EFSCTSIZ	0x2da

#define EVFSCTUI	0x294
#define EVFSCTSI	0x295
#define EVFSCTUF	0x296
#define EVFSCTSF	0x297
#define EVFSCTUIZ	0x298
#define EVFSCTSIZ	0x29a

#define EFDCTUIDZ	0x2ea
#define EFDCTSIDZ	0x2eb

#define EFDCTUI		0x2f4
#define EFDCTSI		0x2f5
#define EFDCTUF		0x2f6
#define EFDCTSF		0x2f7
#define EFDCTUIZ	0x2f8
#define EFDCTSIZ	0x2fa

The emulation code, for the instructions that come in variants
rounding either towards zero or according to the current rounding
direction, uses "if (func & 0x4)" as a condition for using _FP_ROUND
(otherwise _FP_ROUND_ZERO is used).  The condition is correct, but the
code it controls isn't.  Whether _FP_ROUND or _FP_ROUND_ZERO is used
makes no difference, as the effect of those soft-fp macros is to round
an intermediate floating-point result using the low three bits (the
last one sticky) of the working format.  As these operations are
dealing with a freshly unpacked floating-point input, those low bits
are zero and no rounding occurs.  The emulation code then uses the
FP_TO_INT_* macros for the actual integer conversion, with the effect
of always rounding towards zero; for rounding according to the current
rounding direction, it should be using FP_TO_INT_ROUND_*.

The instructions in question have semantics defined (in the Power ISA
documents) for out-of-range values and NaNs: out-of-range values
saturate and NaNs are converted to zero.  The emulation does nothing
to follow those semantics for NaNs (the soft-fp handling is to treat
them as infinities), and messes up the saturation semantics.  For
single-precision conversion to integers, (((func & 0x3) != 0) || SB_s)
is the condition used for doing a signed conversion.  The first part
is correct, but the second isn't: negative numbers should result in
saturation to 0 when converted to unsigned.  Double-precision
conversion to 64-bit integers correctly uses ((func & 0x1) == 0).
Double-precision conversion to 32-bit integers uses (((func & 0x3) !=
0) || DB_s), with correct first part and incorrect second part.  And
vector float conversion to integers uses (((func & 0x3) != 0) ||
SB0_s) (and similar for the other vector element), where the sign bit
check is again wrong.

The incorrect handling of negative numbers converted to unsigned was
introduced in commit afc0a07d4a.  The
rationale given there was a C testcase with cast from float to
unsigned int.  Conversion of out-of-range floating-point numbers to
integer types in C is undefined behavior in the base standard, defined
in Annex F to produce an unspecified value.  That is, the C testcase
used to justify that patch is incorrect - there is no ISO C
requirement for a particular value resulting from this conversion -
and in any case, the correct semantics for such emulation are the
semantics for the instruction (unsigned saturation, which is what it
does in hardware when the emulation is disabled).

The conversion to fixed-point values has its own problems.  That code
doesn't try to do a full emulation; it relies on the trap handler only
being called for arguments that are infinities, NaNs, subnormal or out
of range.  That's fine, but the logic ((vb.wp[1] >> 23) == 0xff &&
((vb.wp[1] & 0x7fffff) > 0)) for NaN detection won't detect negative
NaNs as being NaNs (the same applies for the double-precision case),
and subnormals are mapped to 0 rather than respecting the rounding
mode; the code should also explicitly raise the "invalid" exception.
The code for vectors works by executing the scalar float instruction
with the trapping disabled, meaning at least subnormals won't be
handled correctly.

As well as all those problems in the main emulation code, the rounding
handler - used to emulate rounding upward and downward when not
supported in hardware and when no higher priority exception occurred -
has its own problems.

* It gets called in some cases even for the instructions rounding to
  zero, and then acts according to the current rounding mode when it
  should just leave alone the truncated result provided by hardware.

* It presumes that the result is a single-precision, double-precision
  or single-precision vector as appropriate for the instruction type,
  determines the sign of the result accordingly, and then adjusts the
  result based on that sign and the rounding mode.

  - In the single-precision cases at least the sign determination for
    an integer result is the same as for a floating-point result; in
    the double-precision case, converted to 32-bit integer or fixed
    point, the sign of a double-precision value is in the high part of
    the register but it's the low part of the register that has the
    result of the conversion.

  - If the result is unsigned fixed-point, its sign may be wrongly
    determined as negative (does not actually cause problems, because
    inexact unsigned fixed-point results with the high bit set can
    only appear when converting from double, in which case the sign
    determination is instead wrongly using the high part of the
    register).

  - If the sign of the result is correctly determined as negative, any
    adjustment required to change the truncated result to one correct
    for the rounding mode should be in the opposite direction for
    two's-complement integers as for sign-magnitude floating-point
    values.

  - And if the integer result is zero, the correct sign can only be
    determined by examining the original operand, and not at all (as
    far as I can tell) if the operand and result are the same
    register.

This patch fixes all these problems (as far as possible, given the
inability to determine the correct sign in the rounding handler when
the truncated result is 0, the conversion is to a signed type and the
truncated result has overwritten the original operand).  Conversion to
fixed-point now uses full emulation, and does not use "asm" in the
vector case; the semantics are exactly those of converting to integer
according to the current rounding direction, once the exponent has
been adjusted, so the code makes such an adjustment then uses the
FP_TO_INT_ROUND macros.

The testcase I used for verifying that the instructions (other than
the theoretical conversions to 64-bit integers) produce the correct
results is at <http://lkml.org/lkml/2013/10/8/708>.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:38:59 -06:00
Joseph Myers
d06b3326df math-emu: fix floating-point to integer overflow detection
On overflow, the math-emu macro _FP_TO_INT_ROUND tries to saturate its
result (subject to the value of rsigned specifying the desired
overflow semantics).  However, if the rounding step has the effect of
increasing the exponent so as to cause overflow (if the rounded result
is 1 larger than the largest positive value with the given number of
bits, allowing for signedness), the overflow does not get detected,
meaning that for unsigned results 0 is produced instead of the maximum
unsigned integer with the give number of bits, without an exception
being raised for overflow, and that for signed results the minimum
(negative) value is produced instead of the maximum (positive) value,
again without an exception.  This patch makes the code check for
rounding increasing the exponent and adjusts the exponent value as
needed for the overflow check.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:36:24 -06:00
Joseph Myers
4f6db5efff math-emu: fix floating-point to integer unsigned saturation
The math-emu macros _FP_TO_INT and _FP_TO_INT_ROUND are supposed to
saturate their results for out-of-range arguments, except in the case
rsigned == 2 (when instead the low bits of the result are taken).
However, in the case rsigned == 0 (converting to unsigned integers),
they mistakenly produce 0 for positive results and the maximum
unsigned integer for negative results, the opposite of correct
unsigned saturation.  This patch fixes the logic.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:34:47 -06:00
Joseph Myers
28414a6def powerpc: fix e500 SPE float rounding inexactness detection
The e500 SPE floating-point emulation code for the rounding modes
rounding to positive or negative infinity (which may not be
implemented in hardware) tries to avoid emulating rounding if the
result was inexact.  However, it tests inexactness using the sticky
bit with the cumulative result of previous operations, rather than
with the non-sticky bits relating to the operation that generated the
interrupt.  Furthermore, when a vector operation generates the
interrupt, it's possible that only one of the low and high parts is
inexact, and so only that part should have rounding emulated.  This
results in incorrect rounding of exact results in these modes when the
sticky bit is set from a previous operation.

(I'm not sure why the rounding interrupts are generated at all when
the result is exact, but empirically the hardware does generate them.)

This patch checks for inexactness using the correct bits of SPEFSCR,
and ensures that rounding only occurs when the relevant part of the
result was actually inexact.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:33:48 -06:00
Joseph Myers
640e922501 powerpc: fix exception clearing in e500 SPE float emulation
The e500 SPE floating-point emulation code clears existing exceptions
(__FPU_FPSCR &= ~FP_EX_MASK;) before ORing in the exceptions from the
emulated operation.  However, these exception bits are the "sticky",
cumulative exception bits, and should only be cleared by the user
program setting SPEFSCR, not implicitly by any floating-point
instruction (whether executed purely by the hardware or emulated).
The spurious clearing of these bits shows up as missing exceptions in
glibc testing.

Fixing this, however, is not as simple as just not clearing the bits,
because while the bits may be from previous floating-point operations
(in which case they should not be cleared), the processor can also set
the sticky bits itself before the interrupt for an exception occurs,
and this can happen in cases when IEEE 754 semantics are that the
sticky bit should not be set.  Specifically, the "invalid" sticky bit
is set in various cases with non-finite operands, where IEEE 754
semantics do not involve raising such an exception, and the
"underflow" sticky bit is set in cases of exact underflow, whereas
IEEE 754 semantics are that this flag is set only for inexact
underflow.  Thus, for correct emulation the kernel needs to know the
setting of these two sticky bits before the instruction being
emulated.

When a floating-point operation raises an exception, the kernel can
note the state of the sticky bits immediately afterwards.  Some
<fenv.h> functions that affect the state of these bits, such as
fesetenv and feholdexcept, need to use prctl with PR_GET_FPEXC and
PR_SET_FPEXC anyway, and so it is natural to record the state of those
bits during that call into the kernel and so avoid any need for a
separate call into the kernel to inform it of a change to those bits.
Thus, the interface I chose to use (in this patch and the glibc port)
is that one of those prctl calls must be made after any userspace
change to those sticky bits, other than through a floating-point
operation that traps into the kernel anyway.  feclearexcept and
fesetexceptflag duly make those calls, which would not be required
were it not for this issue.

The previous EGLIBC port, and the uClibc code copied from it, is
fundamentally broken as regards any use of prctl for floating-point
exceptions because it didn't use the PR_FP_EXC_SW_ENABLE bit in its
prctl calls (and did various worse things, such as passing a pointer
when prctl expected an integer).  If you avoid anything where prctl is
used, the clearing of sticky bits still means it will never give
anything approximating correct exception semantics with existing
kernels.  I don't believe the patch makes things any worse for
existing code that doesn't try to inform the kernel of changes to
sticky bits - such code may get incorrect exceptions in some cases,
but it would have done so anyway in other cases.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:32:21 -06:00
Mihai Caraman
228b1a4730 powerpc/booke64: Add LRAT error exception handler
LRAT (Logical to Real Address Translation) present in MMU v2 provides hardware
translation from a logical page number (LPN) to a real page number (RPN) when
tlbwe is executed by a guest or when a page table translation occurs from a
guest virtual address.

Add LRAT error exception handler to Booke3E 64-bit kernel and the basic KVM
handler to avoid build breakage. This is a prerequisite for KVM LRAT support
that will follow.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2014-01-07 18:15:29 -06:00
Benjamin Herrenschmidt
dece8ada99 Merge branch 'merge' into next
Merge a pile of fixes that went into the "merge" branch (3.13-rc's) such
as Anton Little Endian fixes.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 15:19:31 +11:00
Anton Blanchard
a68c33f359 powerpc: Fix endian issues in power7/8 machine check handler
The SLB save area is shared with the hypervisor and is defined
as big endian, so we need to byte swap on little endian builds.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:51:09 +11:00
Benjamin Herrenschmidt
f991db1cf1 Merge remote-tracking branch 'agust/merge' into merge
Anatolij writes:

Please pull two DTS fixes for MPC5125 tower board. Without
them the v3.13-rcX kernels do not boot.
2013-12-30 14:48:27 +11:00
Alistair Popple
d084775738 powerpc/iommu: Update the generic code to use dynamic iommu page sizes
This patch updates the generic iommu backend code to use the
it_page_shift field to determine the iommu page size instead of
using hardcoded values.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:17:19 +11:00
Alistair Popple
3a553170d3 powerpc/iommu: Add it_page_shift field to determine iommu page size
This patch adds a it_page_shift field to struct iommu_table and
initiliases it to 4K for all platforms.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:17:13 +11:00
Alistair Popple
e589a4404f powerpc/iommu: Update constant names to reflect their hardcoded page size
The powerpc iommu uses a hardcoded page size of 4K. This patch changes
the name of the IOMMU_PAGE_* macros to reflect the hardcoded values. A
future patch will use the existing names to support dynamic page
sizes.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:17:06 +11:00
Michael Opdenacker
fee26f6d5d powerpc: Remove unused REDBOOT Kconfig parameter
This removes the REDBOOT Kconfig parameter,
which was no longer used anywhere in the source code
and Makefiles.

Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:17:00 +11:00
Mahesh Salgaonkar
4e243b79b0 powerpc: Fix "attempt to move .org backwards" error
With recent machine check patch series changes, The exception vectors
starting from 0x4300 are now overflowing with allyesconfig. Fix that by
moving machine_check_common and machine_check_handle_early code out of
that region to make enough room for exception vector area.

Fixes this build error reportes by Stephen:

arch/powerpc/kernel/exceptions-64s.S: Assembler messages:
arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards

[Moved the code further down as it introduced link errors due to too long
 relative branches to the masked interrupts handlers from the exception
 prologs. Also removed the useless feature section --BenH
]

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:16:30 +11:00
Olof Johansson
7d4151b509 powerpc: Fix alignment of secondary cpu spin vars
Commit 5c0484e25e ('powerpc: Endian safe trampoline') resulted in
losing proper alignment of the spinlock variables used when booting
secondary CPUs, causing some quite odd issues with failing to boot on
PA Semi-based systems.

This showed itself on ppc64_defconfig, but not on pasemi_defconfig,
so it had gone unnoticed when I initially tested the LE patch set.

Fix is to add explicit alignment instead of relying on good luck. :)

[ It appears that there is a different issue with PA Semi systems
  however this fix is definitely correct so applying anyway -- BenH
]

Fixes: 5c0484e25e ('powerpc: Endian safe trampoline')
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=67811
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:02:34 +11:00
Anton Blanchard
286e4f90a7 powerpc: Align p_end
p_end is an 8 byte value embedded in the text section. This means it
is only 4 byte aligned when it should be 8 byte aligned. Fix this
by adding an explicit alignment.

This fixes an issue where POWER7 little endian builds with
CONFIG_RELOCATABLE=y fail to boot.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:02:33 +11:00
Brian W Hart
ca1de5deb7 powernv/eeh: Add buffer for P7IOC hub error data
Prevent ioda_eeh_hub_diag() from clobbering itself when called by supplying
a per-PHB buffer for P7IOC hub diagnostic data.  Take care to inform OPAL of
the correct size for the buffer.

[Small style change to the use of sizeof -- BenH]

Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:02:32 +11:00
Brian W Hart
20acebdfae powernv/eeh: Fix possible buffer overrun in ioda_eeh_phb_diag()
PHB diagnostic buffer may be smaller than PAGE_SIZE, especially when
PAGE_SIZE > 4KB.

Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-30 14:02:31 +11:00