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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 15:40:25 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 15:40:25 (GMT) |
commit | 5778077d03cb25aac9b6a428e18970642fc019e3 (patch) | |
tree | 2e3f3da1fb99c3646da5ed9a09644696ca5f2309 /drivers/staging | |
parent | 65a99597f044c083983f4274ab049c9ec3b9d764 (diff) | |
parent | 7e01ebffffedec22cea86ebe94802f909e4579ca (diff) | |
download | linux-5778077d03cb25aac9b6a428e18970642fc019e3.tar.xz |
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
"The biggest changes in this cycle were:
- Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC)
primitives. (Andy Lutomirski)
- Add new, comprehensible entry and exit handlers written in C.
(Andy Lutomirski)
- vm86 mode cleanups and fixes. (Brian Gerst)
- 32-bit compat code cleanups. (Brian Gerst)
The amount of simplification in low level assembly code is already
palpable:
arch/x86/entry/entry_32.S | 130 +----
arch/x86/entry/entry_64.S | 197 ++-----
but more simplifications are planned.
There's also the usual laudry mix of low level changes - see the
changelog for details"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits)
x86/asm: Drop repeated macro of X86_EFLAGS_AC definition
x86/asm/msr: Make wrmsrl() a function
x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer
x86/asm: Add MONITORX/MWAITX instruction support
x86/traps: Weaken context tracking entry assertions
x86/asm/tsc: Add rdtscll() merge helper
selftests/x86: Add syscall_nt selftest
selftests/x86: Disable sigreturn_64
x86/vdso: Emit a GNU hash
x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks
x86/entry/32: Migrate to C exit path
x86/entry/32: Remove 32-bit syscall audit optimizations
x86/vm86: Rename vm86->v86flags and v86mask
x86/vm86: Rename vm86->vm86_info to user_vm86
x86/vm86: Clean up vm86.h includes
x86/vm86: Move the vm86 IRQ definitions to vm86.h
x86/vm86: Use the normal pt_regs area for vm86
x86/vm86: Eliminate 'struct kernel_vm86_struct'
x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86'
x86/vm86: Move vm86 fields out of 'thread_struct'
...
Diffstat (limited to 'drivers/staging')
-rw-r--r-- | drivers/staging/media/lirc/lirc_serial.c | 63 |
1 files changed, 4 insertions, 59 deletions
diff --git a/drivers/staging/media/lirc/lirc_serial.c b/drivers/staging/media/lirc/lirc_serial.c index dc79844..465796a 100644 --- a/drivers/staging/media/lirc/lirc_serial.c +++ b/drivers/staging/media/lirc/lirc_serial.c @@ -327,9 +327,6 @@ static void safe_udelay(unsigned long usecs) * time */ -/* So send_pulse can quickly convert microseconds to clocks */ -static unsigned long conv_us_to_clocks; - static int init_timing_params(unsigned int new_duty_cycle, unsigned int new_freq) { @@ -344,7 +341,6 @@ static int init_timing_params(unsigned int new_duty_cycle, /* How many clocks in a microsecond?, avoiding long long divide */ work = loops_per_sec; work *= 4295; /* 4295 = 2^32 / 1e6 */ - conv_us_to_clocks = work >> 32; /* * Carrier period in clocks, approach good up to 32GHz clock, @@ -357,10 +353,9 @@ static int init_timing_params(unsigned int new_duty_cycle, pulse_width = period * duty_cycle / 100; space_width = period - pulse_width; dprintk("in init_timing_params, freq=%d, duty_cycle=%d, " - "clk/jiffy=%ld, pulse=%ld, space=%ld, " - "conv_us_to_clocks=%ld\n", + "clk/jiffy=%ld, pulse=%ld, space=%ld\n", freq, duty_cycle, __this_cpu_read(cpu_info.loops_per_jiffy), - pulse_width, space_width, conv_us_to_clocks); + pulse_width, space_width); return 0; } #else /* ! USE_RDTSC */ @@ -431,63 +426,14 @@ static long send_pulse_irdeo(unsigned long length) return ret; } -#ifdef USE_RDTSC -/* Version that uses Pentium rdtsc instruction to measure clocks */ - -/* - * This version does sub-microsecond timing using rdtsc instruction, - * and does away with the fudged LIRC_SERIAL_TRANSMITTER_LATENCY - * Implicitly i586 architecture... - Steve - */ - -static long send_pulse_homebrew_softcarrier(unsigned long length) -{ - int flag; - unsigned long target, start, now; - - /* Get going quick as we can */ - rdtscl(start); - on(); - /* Convert length from microseconds to clocks */ - length *= conv_us_to_clocks; - /* And loop till time is up - flipping at right intervals */ - now = start; - target = pulse_width; - flag = 1; - /* - * FIXME: This looks like a hard busy wait, without even an occasional, - * polite, cpu_relax() call. There's got to be a better way? - * - * The i2c code has the result of a lot of bit-banging work, I wonder if - * there's something there which could be helpful here. - */ - while ((now - start) < length) { - /* Delay till flip time */ - do { - rdtscl(now); - } while ((now - start) < target); - - /* flip */ - if (flag) { - rdtscl(now); - off(); - target += space_width; - } else { - rdtscl(now); on(); - target += pulse_width; - } - flag = !flag; - } - rdtscl(now); - return ((now - start) - length) / conv_us_to_clocks; -} -#else /* ! USE_RDTSC */ /* Version using udelay() */ /* * here we use fixed point arithmetic, with 8 * fractional bits. that gets us within 0.1% or so of the right average * frequency, albeit with some jitter in pulse length - Steve + * + * This should use ndelay instead. */ /* To match 8 fractional bits used for pulse/space length */ @@ -520,7 +466,6 @@ static long send_pulse_homebrew_softcarrier(unsigned long length) } return (actual-length) >> 8; } -#endif /* USE_RDTSC */ static long send_pulse_homebrew(unsigned long length) { |