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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-12 20:16:56 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-12 20:16:56 +0300
commita26be149facb22d30cd92cadb26f651d6fe802c9 (patch)
treec467bd0cae818ef793e9a694b4cd2bdc88d9ff6b /include/linux/iopoll.h
parentcdd305454ebd181fa35b648c0921fe7df27d6f3b (diff)
parenta20cc76b9efae10c20123049df361adcd7f0e0b3 (diff)
downloadlinux-a26be149facb22d30cd92cadb26f651d6fe802c9.tar.xz
Merge tag 'iommu-updates-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel: "This time with: - Generic page-table framework for ARM IOMMUs using the LPAE page-table format, ARM-SMMU and Renesas IPMMU make use of it already. - Break out the IO virtual address allocator from the Intel IOMMU so that it can be used by other DMA-API implementations too. The first user will be the ARM64 common DMA-API implementation for IOMMUs - Device tree support for Renesas IPMMU - Various fixes and cleanups all over the place" * tag 'iommu-updates-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (36 commits) iommu/amd: Convert non-returned local variable to boolean when relevant iommu: Update my email address iommu/amd: Use wait_event in put_pasid_state_wait iommu/amd: Fix amd_iommu_free_device() iommu/arm-smmu: Avoid build warning iommu/fsl: Various cleanups iommu/fsl: Use %pa to print phys_addr_t iommu/omap: Print phys_addr_t using %pa iommu: Make more drivers depend on COMPILE_TEST iommu/ipmmu-vmsa: Fix IOMMU lookup when multiple IOMMUs are registered iommu: Disable on !MMU builds iommu/fsl: Remove unused fsl_of_pamu_ids[] iommu/fsl: Fix section mismatch iommu/ipmmu-vmsa: Use the ARM LPAE page table allocator iommu: Fix trace_map() to report original iova and original size iommu/arm-smmu: add support for iova_to_phys through ATS1PR iopoll: Introduce memory-mapped IO polling macros iommu/arm-smmu: don't touch the secure STLBIALL register iommu/arm-smmu: make use of generic LPAE allocator iommu: io-pgtable-arm: add non-secure quirk ...
Diffstat (limited to 'include/linux/iopoll.h')
-rw-r--r--include/linux/iopoll.h144
1 files changed, 144 insertions, 0 deletions
diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h
new file mode 100644
index 000000000000..1c30014ed176
--- /dev/null
+++ b/include/linux/iopoll.h
@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _LINUX_IOPOLL_H
+#define _LINUX_IOPOLL_H
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/hrtimer.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+
+/**
+ * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
+ * @op: accessor function (takes @addr as its only argument)
+ * @addr: Address to poll
+ * @val: Variable to read the value into
+ * @cond: Break condition (usually involving @val)
+ * @sleep_us: Maximum time to sleep between reads in us (0
+ * tight-loops). Should be less than ~20ms since usleep_range
+ * is used (see Documentation/timers/timers-howto.txt).
+ * @timeout_us: Timeout in us, 0 means never timeout
+ *
+ * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
+ * case, the last read value at @addr is stored in @val. Must not
+ * be called from atomic context if sleep_us or timeout_us are used.
+ *
+ * When available, you'll probably want to use one of the specialized
+ * macros defined below rather than this macro directly.
+ */
+#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
+({ \
+ ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \
+ might_sleep_if(sleep_us); \
+ for (;;) { \
+ (val) = op(addr); \
+ if (cond) \
+ break; \
+ if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \
+ (val) = op(addr); \
+ break; \
+ } \
+ if (sleep_us) \
+ usleep_range((sleep_us >> 2) + 1, sleep_us); \
+ } \
+ (cond) ? 0 : -ETIMEDOUT; \
+})
+
+/**
+ * readx_poll_timeout_atomic - Periodically poll an address until a condition is met or a timeout occurs
+ * @op: accessor function (takes @addr as its only argument)
+ * @addr: Address to poll
+ * @val: Variable to read the value into
+ * @cond: Break condition (usually involving @val)
+ * @delay_us: Time to udelay between reads in us (0 tight-loops). Should
+ * be less than ~10us since udelay is used (see
+ * Documentation/timers/timers-howto.txt).
+ * @timeout_us: Timeout in us, 0 means never timeout
+ *
+ * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
+ * case, the last read value at @addr is stored in @val.
+ *
+ * When available, you'll probably want to use one of the specialized
+ * macros defined below rather than this macro directly.
+ */
+#define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \
+({ \
+ ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \
+ for (;;) { \
+ (val) = op(addr); \
+ if (cond) \
+ break; \
+ if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \
+ (val) = op(addr); \
+ break; \
+ } \
+ if (delay_us) \
+ udelay(delay_us); \
+ } \
+ (cond) ? 0 : -ETIMEDOUT; \
+})
+
+
+#define readb_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readb, addr, val, cond, delay_us, timeout_us)
+
+#define readb_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readb, addr, val, cond, delay_us, timeout_us)
+
+#define readw_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readw, addr, val, cond, delay_us, timeout_us)
+
+#define readw_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readw, addr, val, cond, delay_us, timeout_us)
+
+#define readl_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readl, addr, val, cond, delay_us, timeout_us)
+
+#define readl_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readl, addr, val, cond, delay_us, timeout_us)
+
+#define readq_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readq, addr, val, cond, delay_us, timeout_us)
+
+#define readq_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readq, addr, val, cond, delay_us, timeout_us)
+
+#define readb_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readb_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readb_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readb_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readw_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readw_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readw_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readw_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readl_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readl_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readq_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout(readq_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define readq_relaxed_poll_timeout_atomic(addr, val, cond, delay_us, timeout_us) \
+ readx_poll_timeout_atomic(readq_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#endif /* _LINUX_IOPOLL_H */