[PATCH v3 7/7] ocxl: Provide global MMIO accessors for external drivers

From: Alastair D'Silva
Date: Mon Mar 25 2019 - 01:45:28 EST


From: Alastair D'Silva <alastair@xxxxxxxxxxx>

External drivers that communicate via OpenCAPI will need to make
MMIO calls to interact with the devices.

Signed-off-by: Alastair D'Silva <alastair@xxxxxxxxxxx>
Reviewed-by: Greg Kurz <groug@xxxxxxxx>
---
drivers/misc/ocxl/Makefile | 2 +-
drivers/misc/ocxl/mmio.c | 234 +++++++++++++++++++++++++++++++++++++
include/misc/ocxl.h | 110 +++++++++++++++++
3 files changed, 345 insertions(+), 1 deletion(-)
create mode 100644 drivers/misc/ocxl/mmio.c

diff --git a/drivers/misc/ocxl/Makefile b/drivers/misc/ocxl/Makefile
index bc4e39bfda7b..d07d1bb8e8d4 100644
--- a/drivers/misc/ocxl/Makefile
+++ b/drivers/misc/ocxl/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0+
ccflags-$(CONFIG_PPC_WERROR) += -Werror

-ocxl-y += main.o pci.o config.o file.o pasid.o
+ocxl-y += main.o pci.o config.o file.o pasid.o mmio.o
ocxl-y += link.o context.o afu_irq.o sysfs.o trace.o
ocxl-y += core.o
obj-$(CONFIG_OCXL) += ocxl.o
diff --git a/drivers/misc/ocxl/mmio.c b/drivers/misc/ocxl/mmio.c
new file mode 100644
index 000000000000..aae713db4ebe
--- /dev/null
+++ b/drivers/misc/ocxl/mmio.c
@@ -0,0 +1,234 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2019 IBM Corp.
+#include <linux/sched/mm.h>
+#include "trace.h"
+#include "ocxl_internal.h"
+
+int ocxl_global_mmio_read32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 *val)
+{
+ if (offset > afu->config.global_mmio_size - 4)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ *val = readl_be((char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ *val = readl((char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_read32);
+
+int ocxl_global_mmio_read64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 *val)
+{
+ if (offset > afu->config.global_mmio_size - 8)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ *val = readq_be((char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ *val = readq((char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_read64);
+
+int ocxl_global_mmio_write32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 val)
+{
+ if (offset > afu->config.global_mmio_size - 4)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ writel_be(val, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ writel(val, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_write32);
+
+int ocxl_global_mmio_write64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 val)
+{
+ if (offset > afu->config.global_mmio_size - 8)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ writeq_be(val, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ writeq(val, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_write64);
+
+int ocxl_global_mmio_set32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 mask)
+{
+ u32 tmp;
+
+ if (offset > afu->config.global_mmio_size - 4)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ tmp = readl_be((char *)afu->global_mmio_ptr + offset);
+ tmp |= mask;
+ writel_be(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ tmp = readl((char *)afu->global_mmio_ptr + offset);
+ tmp |= mask;
+ writel(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_set32);
+
+int ocxl_global_mmio_set64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 mask)
+{
+ u64 tmp;
+
+ if (offset > afu->config.global_mmio_size - 8)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ tmp = readq_be((char *)afu->global_mmio_ptr + offset);
+ tmp |= mask;
+ writeq_be(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ tmp = readq((char *)afu->global_mmio_ptr + offset);
+ tmp |= mask;
+ writeq(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_set64);
+
+int ocxl_global_mmio_clear32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 mask)
+{
+ u32 tmp;
+
+ if (offset > afu->config.global_mmio_size - 4)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ tmp = readl_be((char *)afu->global_mmio_ptr + offset);
+ tmp &= ~mask;
+ writel_be(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ tmp = readl((char *)afu->global_mmio_ptr + offset);
+ tmp &= ~mask;
+ writel(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_clear32);
+
+int ocxl_global_mmio_clear64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 mask)
+{
+ u64 tmp;
+
+ if (offset > afu->config.global_mmio_size - 8)
+ return -EINVAL;
+
+#ifdef __BIG_ENDIAN__
+ if (endian == OCXL_HOST_ENDIAN)
+ endian = OCXL_BIG_ENDIAN;
+#endif
+
+ switch (endian) {
+ case OCXL_BIG_ENDIAN:
+ tmp = readq_be((char *)afu->global_mmio_ptr + offset);
+ tmp &= ~mask;
+ writeq_be(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+
+ default:
+ tmp = readq((char *)afu->global_mmio_ptr + offset);
+ tmp &= ~mask;
+ writeq(tmp, (char *)afu->global_mmio_ptr + offset);
+ break;
+ }
+
+ writeq(tmp, (char *)afu->global_mmio_ptr + offset);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ocxl_global_mmio_clear64);
diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
index 1b48e9d63abb..e0742c00fb72 100644
--- a/include/misc/ocxl.h
+++ b/include/misc/ocxl.h
@@ -45,6 +45,12 @@ struct ocxl_fn_config {
s8 max_afu_index;
};

+enum ocxl_endian {
+ OCXL_BIG_ENDIAN = 0, /**< AFU data is big-endian */
+ OCXL_LITTLE_ENDIAN = 1, /**< AFU data is little-endian */
+ OCXL_HOST_ENDIAN = 2, /**< AFU data is the same endianness as the host */
+};
+
// These are opaque outside the ocxl driver
struct ocxl_afu;
struct ocxl_fn;
@@ -236,6 +242,110 @@ void ocxl_afu_set_private(struct ocxl_afu *afu, void *private);
*/
void *ocxl_afu_get_private(struct ocxl_afu *dev);

+// Global MMIO
+/**
+ * Read a 32 bit value from global MMIO
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @val: returns the value
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_read32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 *val);
+
+/**
+ * Read a 64 bit value from global MMIO
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @val: returns the value
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_read64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 *val);
+
+/**
+ * Write a 32 bit value to global MMIO
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @val: The value to write
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_write32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 val);
+
+/**
+ * Write a 64 bit value to global MMIO
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @val: The value to write
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_write64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 val);
+
+/**
+ * Set bits in a 32 bit global MMIO register
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @mask: a mask of the bits to set
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_set32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 mask);
+
+/**
+ * Set bits in a 64 bit global MMIO register
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @mask: a mask of the bits to set
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_set64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 mask);
+
+/**
+ * Set bits in a 32 bit global MMIO register
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @mask: a mask of the bits to set
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_clear32(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u32 mask);
+
+/**
+ * Set bits in a 64 bit global MMIO register
+ *
+ * @afu: The AFU
+ * @offset: The Offset from the start of MMIO
+ * @endian: the endianness that the MMIO data is in
+ * @mask: a mask of the bits to set
+ *
+ * Returns 0 for success, negative on error
+ */
+int ocxl_global_mmio_clear64(struct ocxl_afu *afu, size_t offset,
+ enum ocxl_endian endian, u64 mask);

// Functions left here are for compatibility with the cxlflash driver

--
2.20.1