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| author | Mike Frysinger <vapier@gentoo.org> | 2010-04-22 21:15:00 +0000 |
|---|---|---|
| committer | Mike Frysinger <vapier@gentoo.org> | 2010-05-22 14:19:09 -0400 |
| commit | 80fcdb959343ab9e0ee95c11b5ea47c44a2c3004 (patch) | |
| tree | 16d44c1fb014d3b9856d65c7bd8966d35a3719b2 /arch | |
| parent | 11cabcb95e0d9de15f3d8a9d25336edfc5444337 (diff) | |
| download | linux-80fcdb959343ab9e0ee95c11b5ea47c44a2c3004.tar.gz linux-80fcdb959343ab9e0ee95c11b5ea47c44a2c3004.tar.bz2 linux-80fcdb959343ab9e0ee95c11b5ea47c44a2c3004.zip | |
Blackfin: SIC: cut down on IAR MMR reads a bit
Tweak the for loops that operate on the SIC IAR system MMRs to avoid
re-reading them multiple times in a row. System MMRs are a little
slower to access, so avoid the penalty when possible.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/blackfin/mach-common/ints-priority.c | 33 |
1 files changed, 18 insertions, 15 deletions
diff --git a/arch/blackfin/mach-common/ints-priority.c b/arch/blackfin/mach-common/ints-priority.c index ce988713445d..1c8c4c7245c3 100644 --- a/arch/blackfin/mach-common/ints-priority.c +++ b/arch/blackfin/mach-common/ints-priority.c @@ -92,26 +92,29 @@ static void __init search_IAR(void) { unsigned ivg, irq_pos = 0; for (ivg = 0; ivg <= IVG13 - IVG7; ivg++) { - int irqn; + int irqN; ivg7_13[ivg].istop = ivg7_13[ivg].ifirst = &ivg_table[irq_pos]; - for (irqn = 0; irqn < NR_PERI_INTS; irqn++) { - int iar_shift = (irqn & 7) * 4; - if (ivg == (0xf & -#if defined(CONFIG_BF52x) || defined(CONFIG_BF538) \ - || defined(CONFIG_BF539) || defined(CONFIG_BF51x) - bfin_read32((unsigned long *)SIC_IAR0 + - ((irqn % 32) >> 3) + ((irqn / 32) * - ((SIC_IAR4 - SIC_IAR0) / 4))) >> iar_shift)) { + for (irqN = 0; irqN < NR_PERI_INTS; irqN += 4) { + int irqn; + u32 iar = bfin_read32((unsigned long *)SIC_IAR0 + +#if defined(CONFIG_BF51x) || defined(CONFIG_BF52x) || \ + defined(CONFIG_BF538) || defined(CONFIG_BF539) + ((irqN % 32) >> 3) + ((irqN / 32) * ((SIC_IAR4 - SIC_IAR0) / 4)) #else - bfin_read32((unsigned long *)SIC_IAR0 + - (irqn >> 3)) >> iar_shift)) { + (irqN >> 3) #endif - ivg_table[irq_pos].irqno = IVG7 + irqn; - ivg_table[irq_pos].isrflag = 1 << (irqn % 32); - ivg7_13[ivg].istop++; - irq_pos++; + ); + + for (irqn = irqN; irqn < irqN + 4; ++irqn) { + int iar_shift = (irqn & 7) * 4; + if (ivg == (0xf & (iar >> iar_shift))) { + ivg_table[irq_pos].irqno = IVG7 + irqn; + ivg_table[irq_pos].isrflag = 1 << (irqn % 32); + ivg7_13[ivg].istop++; + irq_pos++; + } } } } |