1 files changed, 67 insertions, 0 deletions
diff --git a/lib/crc/s390/crc32.h b/lib/crc/s390/crc32.h
new file mode 100644
index 000000000000..59c8983d428b
--- /dev/null
+++ b/lib/crc/s390/crc32.h
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CRC-32 implemented with the z/Architecture Vector Extension Facility.
+ *
+ * Copyright IBM Corp. 2015
+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+
+#include <linux/cpufeature.h>
+#include <asm/fpu.h>
+#include "crc32-vx.h"
+
+#define VX_MIN_LEN		64
+#define VX_ALIGNMENT		16L
+#define VX_ALIGN_MASK		(VX_ALIGNMENT - 1)
+
+/*
+ * DEFINE_CRC32_VX() - Define a CRC-32 function using the vector extension
+ *
+ * Creates a function to perform a particular CRC-32 computation. Depending
+ * on the message buffer, the hardware-accelerated or software implementation
+ * is used.   Note that the message buffer is aligned to improve fetch
+ * operations of VECTOR LOAD MULTIPLE instructions.
+ */
+#define DEFINE_CRC32_VX(___fname, ___crc32_vx, ___crc32_sw)		    \
+	static inline u32 ___fname(u32 crc, const u8 *data, size_t datalen) \
+	{								    \
+		unsigned long prealign, aligned, remaining;		    \
+		DECLARE_KERNEL_FPU_ONSTACK16(vxstate);			    \
+									    \
+		if (datalen < VX_MIN_LEN + VX_ALIGN_MASK || !cpu_has_vx())  \
+			return ___crc32_sw(crc, data, datalen);		    \
+									    \
+		if ((unsigned long)data & VX_ALIGN_MASK) {		    \
+			prealign = VX_ALIGNMENT -			    \
+				  ((unsigned long)data & VX_ALIGN_MASK);    \
+			datalen -= prealign;				    \
+			crc = ___crc32_sw(crc, data, prealign);		    \
+			data = (void *)((unsigned long)data + prealign);    \
+		}							    \
+									    \
+		aligned = datalen & ~VX_ALIGN_MASK;			    \
+		remaining = datalen & VX_ALIGN_MASK;			    \
+									    \
+		kernel_fpu_begin(&vxstate, KERNEL_VXR_LOW);		    \
+		crc = ___crc32_vx(crc, data, aligned);			    \
+		kernel_fpu_end(&vxstate, KERNEL_VXR_LOW);		    \
+									    \
+		if (remaining)						    \
+			crc = ___crc32_sw(crc, data + aligned, remaining);  \
+									    \
+		return crc;						    \
+	}
+
+DEFINE_CRC32_VX(crc32_le_arch, crc32_le_vgfm_16, crc32_le_base)
+DEFINE_CRC32_VX(crc32_be_arch, crc32_be_vgfm_16, crc32_be_base)
+DEFINE_CRC32_VX(crc32c_arch, crc32c_le_vgfm_16, crc32c_base)
+
+static inline u32 crc32_optimizations_arch(void)
+{
+	if (cpu_has_vx()) {
+		return CRC32_LE_OPTIMIZATION |
+		       CRC32_BE_OPTIMIZATION |
+		       CRC32C_OPTIMIZATION;
+	}
+	return 0;
+}