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authorPeter Maydell2016-06-17 17:16:37 +0200
committerPeter Maydell2016-06-17 17:16:37 +0200
commit482b61844ae7c6df39df0b48ac90ffbc87bed7d2 (patch)
treef3344170f132d6c8f01e4693496a37827b654c15 /include/qemu/bitops.h
parentMerge remote-tracking branch 'remotes/ehabkost/tags/machine-pull-request' int... (diff)
parentACPI: ARM: Present GIC version in MADT table (diff)
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20160617' into staging
target-arm queue: * GICv3 emulation # gpg: Signature made Fri 17 Jun 2016 15:24:28 BST # gpg: using RSA key 0x3C2525ED14360CDE # gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" # gpg: aka "Peter Maydell <pmaydell@gmail.com>" # gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" # Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE * remotes/pmaydell/tags/pull-target-arm-20160617: (22 commits) ACPI: ARM: Present GIC version in MADT table hw/timer: Add value matching support to aspeed_timer target-arm/monitor.c: Advertise emulated GICv3 in capabilities target-arm/machine.c: Allow user to request GICv3 emulation hw/intc/arm_gicv3: Add IRQ handling CPU interface registers hw/intc/arm_gicv3: Implement CPU i/f SGI generation registers hw/intc/arm_gicv3: Implement gicv3_cpuif_update() hw/intc/arm_gicv3: Implement GICv3 CPU interface registers hw/intc/arm_gicv3: Implement gicv3_set_irq() hw/intc/arm_gicv3: Wire up distributor and redistributor MMIO regions hw/intc/arm_gicv3: Implement GICv3 redistributor registers hw/intc/arm_gicv3: Implement GICv3 distributor registers hw/intc/arm_gicv3: Implement functions to identify next pending irq hw/intc/arm_gicv3: ARM GICv3 device framework hw/intc/arm_gicv3: Add vmstate descriptors hw/intc/arm_gicv3: Move irq lines into GICv3CPUState structure hw/intc/arm_gicv3: Add state information target-arm: Add mp-affinity property for ARM CPU class target-arm: Provide hook to tell GICv3 about changes of security state target-arm: Define new arm_is_el3_or_mon() function ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'include/qemu/bitops.h')
-rw-r--r--include/qemu/bitops.h108
1 files changed, 108 insertions, 0 deletions
diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h
index 755fdd1293..15418a86df 100644
--- a/include/qemu/bitops.h
+++ b/include/qemu/bitops.h
@@ -428,4 +428,112 @@ static inline uint64_t deposit64(uint64_t value, int start, int length,
return (value & ~mask) | ((fieldval << start) & mask);
}
+/**
+ * half_shuffle32:
+ * @value: 32-bit value (of which only the bottom 16 bits are of interest)
+ *
+ * Given an input value:
+ * xxxx xxxx xxxx xxxx ABCD EFGH IJKL MNOP
+ * return the value where the bottom 16 bits are spread out into
+ * the odd bits in the word, and the even bits are zeroed:
+ * 0A0B 0C0D 0E0F 0G0H 0I0J 0K0L 0M0N 0O0P
+ *
+ * Any bits set in the top half of the input are ignored.
+ *
+ * Returns: the shuffled bits.
+ */
+static inline uint32_t half_shuffle32(uint32_t x)
+{
+ /* This algorithm is from _Hacker's Delight_ section 7-2 "Shuffling Bits".
+ * It ignores any bits set in the top half of the input.
+ */
+ x = ((x & 0xFF00) << 8) | (x & 0x00FF);
+ x = ((x << 4) | x) & 0x0F0F0F0F;
+ x = ((x << 2) | x) & 0x33333333;
+ x = ((x << 1) | x) & 0x55555555;
+ return x;
+}
+
+/**
+ * half_shuffle64:
+ * @value: 64-bit value (of which only the bottom 32 bits are of interest)
+ *
+ * Given an input value:
+ * xxxx xxxx xxxx .... xxxx xxxx ABCD EFGH IJKL MNOP QRST UVWX YZab cdef
+ * return the value where the bottom 32 bits are spread out into
+ * the odd bits in the word, and the even bits are zeroed:
+ * 0A0B 0C0D 0E0F 0G0H 0I0J 0K0L 0M0N .... 0U0V 0W0X 0Y0Z 0a0b 0c0d 0e0f
+ *
+ * Any bits set in the top half of the input are ignored.
+ *
+ * Returns: the shuffled bits.
+ */
+static inline uint64_t half_shuffle64(uint64_t x)
+{
+ /* This algorithm is from _Hacker's Delight_ section 7-2 "Shuffling Bits".
+ * It ignores any bits set in the top half of the input.
+ */
+ x = ((x & 0xFFFF0000ULL) << 16) | (x & 0xFFFF);
+ x = ((x << 8) | x) & 0x00FF00FF00FF00FFULL;
+ x = ((x << 4) | x) & 0x0F0F0F0F0F0F0F0FULL;
+ x = ((x << 2) | x) & 0x3333333333333333ULL;
+ x = ((x << 1) | x) & 0x5555555555555555ULL;
+ return x;
+}
+
+/**
+ * half_unshuffle32:
+ * @value: 32-bit value (of which only the odd bits are of interest)
+ *
+ * Given an input value:
+ * xAxB xCxD xExF xGxH xIxJ xKxL xMxN xOxP
+ * return the value where all the odd bits are compressed down
+ * into the low half of the word, and the high half is zeroed:
+ * 0000 0000 0000 0000 ABCD EFGH IJKL MNOP
+ *
+ * Any even bits set in the input are ignored.
+ *
+ * Returns: the unshuffled bits.
+ */
+static inline uint32_t half_unshuffle32(uint32_t x)
+{
+ /* This algorithm is from _Hacker's Delight_ section 7-2 "Shuffling Bits".
+ * where it is called an inverse half shuffle.
+ */
+ x &= 0x55555555;
+ x = ((x >> 1) | x) & 0x33333333;
+ x = ((x >> 2) | x) & 0x0F0F0F0F;
+ x = ((x >> 4) | x) & 0x00FF00FF;
+ x = ((x >> 8) | x) & 0x0000FFFF;
+ return x;
+}
+
+/**
+ * half_unshuffle64:
+ * @value: 64-bit value (of which only the odd bits are of interest)
+ *
+ * Given an input value:
+ * xAxB xCxD xExF xGxH xIxJ xKxL xMxN .... xUxV xWxX xYxZ xaxb xcxd xexf
+ * return the value where all the odd bits are compressed down
+ * into the low half of the word, and the high half is zeroed:
+ * 0000 0000 0000 .... 0000 0000 ABCD EFGH IJKL MNOP QRST UVWX YZab cdef
+ *
+ * Any even bits set in the input are ignored.
+ *
+ * Returns: the unshuffled bits.
+ */
+static inline uint64_t half_unshuffle64(uint64_t x)
+{
+ /* This algorithm is from _Hacker's Delight_ section 7-2 "Shuffling Bits".
+ * where it is called an inverse half shuffle.
+ */
+ x &= 0x5555555555555555ULL;
+ x = ((x >> 1) | x) & 0x3333333333333333ULL;
+ x = ((x >> 2) | x) & 0x0F0F0F0F0F0F0F0FULL;
+ x = ((x >> 4) | x) & 0x00FF00FF00FF00FFULL;
+ x = ((x >> 8) | x) & 0x0000FFFF0000FFFFULL;
+ x = ((x >> 16) | x) & 0x00000000FFFFFFFFULL;
+ return x;
+}
+
#endif