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authorOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
committerOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
commit2e6185f1fea6cf88e9ce25cde1d6291ddfb3d4f0 (patch)
treec45ae7bace055c258fba5c4c6c0340b1e3f17f05 /arch/alpha/lib/strncpy_from_user.S
parent7405a749ae14f846cc2892c36d1a9343b0264b7c (diff)
parentfd301cc4e5ba839050be135a178031bcd0d363a5 (diff)
Merge tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/drivers
From Stephen Warren: ARM: tegra: i2c driver enhancements mostly related to clocking This branch contains a number of fixes and cleanups to the Tegra I2C driver related to clocks. These are based on the common clock conversion in order to avoid duplicating the clock driver changes before and after the conversion. Finally, a bug-fix related to I2C_M_NOSTART is included. This branch is based on previous pull request tegra-for-3.7-common-clk. * tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: i2c: tegra: dynamically control fast clk i2c: tegra: I2_M_NOSTART functionality not supported in Tegra20 ARM: tegra: clock: remove unused clock entry for i2c ARM: tegra: clock: add connection name in i2c clock entry i2c: tegra: pass proper name for getting clock ARM: tegra: clock: add i2c fast clock entry in clock table ARM: Tegra: Add smp_twd clock for Tegra20 ARM: tegra: cpu-tegra: explicitly manage re-parenting ARM: tegra: fix overflow in tegra20_pll_clk_round_rate() ARM: tegra: Fix data type for io address ARM: tegra: remove tegra_timer from tegra_list_clks ARM: tegra30: clocks: fix the wrong tegra_audio_sync_clk_ops name ARM: tegra: clocks: separate tegra_clk_32k_ops from Tegra20 and Tegra30 ARM: tegra: Remove duplicate code ARM: tegra: Port tegra to generic clock framework ARM: tegra: Add clk_tegra structure and helper functions ARM: tegra: Rename tegra20 clock file ARM: tegra20: Separate out clk ops and clk data ARM: tegra30: Separate out clk ops and clk data ARM: tegra: fix U16 divider range check ... + sync to v3.6-rc4 Resolved remove/modify conflict in arch/arm/mach-sa1100/leds-hackkit.c caused by the sync with v3.6-rc4. Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/alpha/lib/strncpy_from_user.S')
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diff --git a/arch/alpha/lib/strncpy_from_user.S b/arch/alpha/lib/strncpy_from_user.S
deleted file mode 100644
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--- a/arch/alpha/lib/strncpy_from_user.S
+++ /dev/null
@@ -1,339 +0,0 @@
-/*
- * arch/alpha/lib/strncpy_from_user.S
- * Contributed by Richard Henderson (rth@tamu.edu)
- *
- * Just like strncpy except in the return value:
- *
- * -EFAULT if an exception occurs before the terminator is copied.
- * N if the buffer filled.
- *
- * Otherwise the length of the string is returned.
- */
-
-
-#include <asm/errno.h>
-#include <asm/regdef.h>
-
-
-/* Allow an exception for an insn; exit if we get one. */
-#define EX(x,y...) \
- 99: x,##y; \
- .section __ex_table,"a"; \
- .long 99b - .; \
- lda $31, $exception-99b($0); \
- .previous
-
-
- .set noat
- .set noreorder
- .text
-
- .globl __strncpy_from_user
- .ent __strncpy_from_user
- .frame $30, 0, $26
- .prologue 0
-
- .align 3
-$aligned:
- /* On entry to this basic block:
- t0 == the first destination word for masking back in
- t1 == the first source word. */
-
- /* Create the 1st output word and detect 0's in the 1st input word. */
- lda t2, -1 # e1 : build a mask against false zero
- mskqh t2, a1, t2 # e0 : detection in the src word
- mskqh t1, a1, t3 # e0 :
- ornot t1, t2, t2 # .. e1 :
- mskql t0, a1, t0 # e0 : assemble the first output word
- cmpbge zero, t2, t8 # .. e1 : bits set iff null found
- or t0, t3, t0 # e0 :
- beq a2, $a_eoc # .. e1 :
- bne t8, $a_eos # .. e1 :
-
- /* On entry to this basic block:
- t0 == a source word not containing a null. */
-
-$a_loop:
- stq_u t0, 0(a0) # e0 :
- addq a0, 8, a0 # .. e1 :
- EX( ldq_u t0, 0(a1) ) # e0 :
- addq a1, 8, a1 # .. e1 :
- subq a2, 1, a2 # e0 :
- cmpbge zero, t0, t8 # .. e1 (stall)
- beq a2, $a_eoc # e1 :
- beq t8, $a_loop # e1 :
-
- /* Take care of the final (partial) word store. At this point
- the end-of-count bit is set in t8 iff it applies.
-
- On entry to this basic block we have:
- t0 == the source word containing the null
- t8 == the cmpbge mask that found it. */
-
-$a_eos:
- negq t8, t12 # e0 : find low bit set
- and t8, t12, t12 # e1 (stall)
-
- /* For the sake of the cache, don't read a destination word
- if we're not going to need it. */
- and t12, 0x80, t6 # e0 :
- bne t6, 1f # .. e1 (zdb)
-
- /* We're doing a partial word store and so need to combine
- our source and original destination words. */
- ldq_u t1, 0(a0) # e0 :
- subq t12, 1, t6 # .. e1 :
- or t12, t6, t8 # e0 :
- unop #
- zapnot t0, t8, t0 # e0 : clear src bytes > null
- zap t1, t8, t1 # .. e1 : clear dst bytes <= null
- or t0, t1, t0 # e1 :
-
-1: stq_u t0, 0(a0)
- br $finish_up
-
- /* Add the end-of-count bit to the eos detection bitmask. */
-$a_eoc:
- or t10, t8, t8
- br $a_eos
-
- /*** The Function Entry Point ***/
- .align 3
-__strncpy_from_user:
- mov a0, v0 # save the string start
- beq a2, $zerolength
-
- /* Are source and destination co-aligned? */
- xor a0, a1, t1 # e0 :
- and a0, 7, t0 # .. e1 : find dest misalignment
- and t1, 7, t1 # e0 :
- addq a2, t0, a2 # .. e1 : bias count by dest misalignment
- subq a2, 1, a2 # e0 :
- and a2, 7, t2 # e1 :
- srl a2, 3, a2 # e0 : a2 = loop counter = (count - 1)/8
- addq zero, 1, t10 # .. e1 :
- sll t10, t2, t10 # e0 : t10 = bitmask of last count byte
- bne t1, $unaligned # .. e1 :
-
- /* We are co-aligned; take care of a partial first word. */
-
- EX( ldq_u t1, 0(a1) ) # e0 : load first src word
- addq a1, 8, a1 # .. e1 :
-
- beq t0, $aligned # avoid loading dest word if not needed
- ldq_u t0, 0(a0) # e0 :
- br $aligned # .. e1 :
-
-
-/* The source and destination are not co-aligned. Align the destination
- and cope. We have to be very careful about not reading too much and
- causing a SEGV. */
-
- .align 3
-$u_head:
- /* We know just enough now to be able to assemble the first
- full source word. We can still find a zero at the end of it
- that prevents us from outputting the whole thing.
-
- On entry to this basic block:
- t0 == the first dest word, unmasked
- t1 == the shifted low bits of the first source word
- t6 == bytemask that is -1 in dest word bytes */
-
- EX( ldq_u t2, 8(a1) ) # e0 : load second src word
- addq a1, 8, a1 # .. e1 :
- mskql t0, a0, t0 # e0 : mask trailing garbage in dst
- extqh t2, a1, t4 # e0 :
- or t1, t4, t1 # e1 : first aligned src word complete
- mskqh t1, a0, t1 # e0 : mask leading garbage in src
- or t0, t1, t0 # e0 : first output word complete
- or t0, t6, t6 # e1 : mask original data for zero test
- cmpbge zero, t6, t8 # e0 :
- beq a2, $u_eocfin # .. e1 :
- bne t8, $u_final # e1 :
-
- lda t6, -1 # e1 : mask out the bits we have
- mskql t6, a1, t6 # e0 : already seen
- stq_u t0, 0(a0) # e0 : store first output word
- or t6, t2, t2 # .. e1 :
- cmpbge zero, t2, t8 # e0 : find nulls in second partial
- addq a0, 8, a0 # .. e1 :
- subq a2, 1, a2 # e0 :
- bne t8, $u_late_head_exit # .. e1 :
-
- /* Finally, we've got all the stupid leading edge cases taken care
- of and we can set up to enter the main loop. */
-
- extql t2, a1, t1 # e0 : position hi-bits of lo word
- EX( ldq_u t2, 8(a1) ) # .. e1 : read next high-order source word
- addq a1, 8, a1 # e0 :
- cmpbge zero, t2, t8 # e1 (stall)
- beq a2, $u_eoc # e1 :
- bne t8, $u_eos # e1 :
-
- /* Unaligned copy main loop. In order to avoid reading too much,
- the loop is structured to detect zeros in aligned source words.
- This has, unfortunately, effectively pulled half of a loop
- iteration out into the head and half into the tail, but it does
- prevent nastiness from accumulating in the very thing we want
- to run as fast as possible.
-
- On entry to this basic block:
- t1 == the shifted high-order bits from the previous source word
- t2 == the unshifted current source word
-
- We further know that t2 does not contain a null terminator. */
-
- .align 3
-$u_loop:
- extqh t2, a1, t0 # e0 : extract high bits for current word
- addq a1, 8, a1 # .. e1 :
- extql t2, a1, t3 # e0 : extract low bits for next time
- addq a0, 8, a0 # .. e1 :
- or t0, t1, t0 # e0 : current dst word now complete
- EX( ldq_u t2, 0(a1) ) # .. e1 : load high word for next time
- stq_u t0, -8(a0) # e0 : save the current word
- mov t3, t1 # .. e1 :
- subq a2, 1, a2 # e0 :
- cmpbge zero, t2, t8 # .. e1 : test new word for eos
- beq a2, $u_eoc # e1 :
- beq t8, $u_loop # e1 :
-
- /* We've found a zero somewhere in the source word we just read.
- If it resides in the lower half, we have one (probably partial)
- word to write out, and if it resides in the upper half, we
- have one full and one partial word left to write out.
-
- On entry to this basic block:
- t1 == the shifted high-order bits from the previous source word
- t2 == the unshifted current source word. */
-$u_eos:
- extqh t2, a1, t0 # e0 :
- or t0, t1, t0 # e1 : first (partial) source word complete
-
- cmpbge zero, t0, t8 # e0 : is the null in this first bit?
- bne t8, $u_final # .. e1 (zdb)
-
- stq_u t0, 0(a0) # e0 : the null was in the high-order bits
- addq a0, 8, a0 # .. e1 :
- subq a2, 1, a2 # e1 :
-
-$u_late_head_exit:
- extql t2, a1, t0 # .. e0 :
- cmpbge zero, t0, t8 # e0 :
- or t8, t10, t6 # e1 :
- cmoveq a2, t6, t8 # e0 :
- nop # .. e1 :
-
- /* Take care of a final (probably partial) result word.
- On entry to this basic block:
- t0 == assembled source word
- t8 == cmpbge mask that found the null. */
-$u_final:
- negq t8, t6 # e0 : isolate low bit set
- and t6, t8, t12 # e1 :
-
- and t12, 0x80, t6 # e0 : avoid dest word load if we can
- bne t6, 1f # .. e1 (zdb)
-
- ldq_u t1, 0(a0) # e0 :
- subq t12, 1, t6 # .. e1 :
- or t6, t12, t8 # e0 :
- zapnot t0, t8, t0 # .. e1 : kill source bytes > null
- zap t1, t8, t1 # e0 : kill dest bytes <= null
- or t0, t1, t0 # e1 :
-
-1: stq_u t0, 0(a0) # e0 :
- br $finish_up
-
-$u_eoc: # end-of-count
- extqh t2, a1, t0
- or t0, t1, t0
- cmpbge zero, t0, t8
-
-$u_eocfin: # end-of-count, final word
- or t10, t8, t8
- br $u_final
-
- /* Unaligned copy entry point. */
- .align 3
-$unaligned:
-
- EX( ldq_u t1, 0(a1) ) # e0 : load first source word
-
- and a0, 7, t4 # .. e1 : find dest misalignment
- and a1, 7, t5 # e0 : find src misalignment
-
- /* Conditionally load the first destination word and a bytemask
- with 0xff indicating that the destination byte is sacrosanct. */
-
- mov zero, t0 # .. e1 :
- mov zero, t6 # e0 :
- beq t4, 1f # .. e1 :
- ldq_u t0, 0(a0) # e0 :
- lda t6, -1 # .. e1 :
- mskql t6, a0, t6 # e0 :
-1:
- subq a1, t4, a1 # .. e1 : sub dest misalignment from src addr
-
- /* If source misalignment is larger than dest misalignment, we need
- extra startup checks to avoid SEGV. */
-
- cmplt t4, t5, t12 # e1 :
- extql t1, a1, t1 # .. e0 : shift src into place
- lda t2, -1 # e0 : for creating masks later
- beq t12, $u_head # e1 :
-
- mskqh t2, t5, t2 # e0 : begin src byte validity mask
- cmpbge zero, t1, t8 # .. e1 : is there a zero?
- extql t2, a1, t2 # e0 :
- or t8, t10, t5 # .. e1 : test for end-of-count too
- cmpbge zero, t2, t3 # e0 :
- cmoveq a2, t5, t8 # .. e1 :
- andnot t8, t3, t8 # e0 :
- beq t8, $u_head # .. e1 (zdb)
-
- /* At this point we've found a zero in the first partial word of
- the source. We need to isolate the valid source data and mask
- it into the original destination data. (Incidentally, we know
- that we'll need at least one byte of that original dest word.) */
-
- ldq_u t0, 0(a0) # e0 :
- negq t8, t6 # .. e1 : build bitmask of bytes <= zero
- mskqh t1, t4, t1 # e0 :
- and t6, t8, t12 # .. e1 :
- subq t12, 1, t6 # e0 :
- or t6, t12, t8 # e1 :
-
- zapnot t2, t8, t2 # e0 : prepare source word; mirror changes
- zapnot t1, t8, t1 # .. e1 : to source validity mask
-
- andnot t0, t2, t0 # e0 : zero place for source to reside
- or t0, t1, t0 # e1 : and put it there
- stq_u t0, 0(a0) # e0 :
-
-$finish_up:
- zapnot t0, t12, t4 # was last byte written null?
- cmovne t4, 1, t4
-
- and t12, 0xf0, t3 # binary search for the address of the
- and t12, 0xcc, t2 # last byte written
- and t12, 0xaa, t1
- bic a0, 7, t0
- cmovne t3, 4, t3
- cmovne t2, 2, t2
- cmovne t1, 1, t1
- addq t0, t3, t0
- addq t1, t2, t1
- addq t0, t1, t0
- addq t0, t4, t0 # add one if we filled the buffer
-
- subq t0, v0, v0 # find string length
- ret
-
-$zerolength:
- clr v0
-$exception:
- ret
-
- .end __strncpy_from_user