isci: uplevel register hardware data structures and unsolicited frame handling

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 357 insertions, 0 deletions

diff --git a/drivers/scsi/isci/unsolicited_frame_control.c b/drivers/scsi/isci/unsolicited_frame_control.c
new file mode 100644
index 000000000000..8d68dcc52bc1
--- /dev/null
+++ b/drivers/scsi/isci/unsolicited_frame_control.c
@@ -0,0 +1,357 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "host.h"
+#include "unsolicited_frame_control.h"
+#include "registers.h"
+#include "sci_util.h"
+
+/**
+ * This method will program the unsolicited frames (UFs) into the UF address
+ *    table and construct the UF frame structure being modeled in the core.  It
+ *    will handle the case where some of the UFs are not being used and thus
+ *    should have entries programmed to zero in the address table.
+ * @uf_control: This parameter specifies the unsolicted frame control object
+ *    for which to construct the unsolicited frames objects.
+ * @uf_buffer_phys_address: This parameter specifies the physical address for
+ *    the first unsolicited frame buffer.
+ * @uf_buffer_virt_address: This parameter specifies the virtual address for
+ *    the first unsolicited frame buffer.
+ * @unused_uf_header_entries: This parameter specifies the number of unused UF
+ *    headers.  This value can be non-zero when there are a non-power of 2
+ *    number of unsolicited frames being supported.
+ * @used_uf_header_entries: This parameter specifies the number of actually
+ *    utilized UF headers.
+ *
+ */
+static void scic_sds_unsolicited_frame_control_construct_frames(
+	struct scic_sds_unsolicited_frame_control *uf_control,
+	dma_addr_t uf_buffer_phys_address,
+	void *uf_buffer_virt_address,
+	u32 unused_uf_header_entries,
+	u32 used_uf_header_entries)
+{
+	u32 index;
+	struct scic_sds_unsolicited_frame *uf;
+
+	/*
+	 * Program the unused buffers into the UF address table and the
+	 * controller's array of UFs.
+	 */
+	for (index = 0; index < unused_uf_header_entries; index++) {
+		uf = &uf_control->buffers.array[index];
+
+		sci_cb_make_physical_address(
+			uf_control->address_table.array[index], 0, 0
+			);
+		uf->buffer = NULL;
+		uf->header = &uf_control->headers.array[index];
+		uf->state  = UNSOLICITED_FRAME_EMPTY;
+	}
+
+	/*
+	 * Program the actual used UF buffers into the UF address table and
+	 * the controller's array of UFs.
+	 */
+	for (index = unused_uf_header_entries;
+	     index < unused_uf_header_entries + used_uf_header_entries;
+	     index++) {
+		uf = &uf_control->buffers.array[index];
+
+		uf_control->address_table.array[index] = uf_buffer_phys_address;
+
+		uf->buffer = uf_buffer_virt_address;
+		uf->header = &uf_control->headers.array[index];
+		uf->state  = UNSOLICITED_FRAME_EMPTY;
+
+		/*
+		 * Increment the address of the physical and virtual memory
+		 * pointers. Everything is aligned on 1k boundary with an
+		 * increment of 1k.
+		 */
+		uf_buffer_virt_address += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
+		uf_buffer_phys_address += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
+	}
+}
+
+int scic_sds_unsolicited_frame_control_construct(struct scic_sds_controller *scic)
+{
+	struct scic_sds_unsolicited_frame_control *uf_control = &scic->uf_control;
+	u32 unused_uf_header_entries;
+	u32 used_uf_header_entries;
+	u32 used_uf_buffer_bytes;
+	u32 unused_uf_header_bytes;
+	u32 used_uf_header_bytes;
+	dma_addr_t uf_buffer_phys_address;
+	void *uf_buffer_virt_address;
+	size_t size;
+
+	/*
+	 * The UF buffer address table size must be programmed to a power
+	 * of 2.  Find the first power of 2 that is equal to or greater then
+	 * the number of unsolicited frame buffers to be utilized.
+	 */
+	uf_control->address_table.count = SCU_MIN_UF_TABLE_ENTRIES;
+	while (uf_control->address_table.count < uf_control->buffers.count &&
+	       uf_control->address_table.count < SCU_ABSOLUTE_MAX_UNSOLICITED_FRAMES)
+		uf_control->address_table.count <<= 1;
+
+	/*
+	 * Prepare all of the memory sizes for the UF headers, UF address
+	 * table, and UF buffers themselves.
+	 */
+	used_uf_buffer_bytes     = uf_control->buffers.count
+				   * SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
+	unused_uf_header_entries = uf_control->address_table.count
+				   - uf_control->buffers.count;
+	used_uf_header_entries   = uf_control->buffers.count;
+	unused_uf_header_bytes   = unused_uf_header_entries
+				   * sizeof(struct scu_unsolicited_frame_header);
+	used_uf_header_bytes     = used_uf_header_entries
+				   * sizeof(struct scu_unsolicited_frame_header);
+
+	size = used_uf_buffer_bytes + used_uf_header_bytes +
+			uf_control->address_table.count * sizeof(dma_addr_t);
+
+
+	/*
+	 * The Unsolicited Frame buffers are set at the start of the UF
+	 * memory descriptor entry. The headers and address table will be
+	 * placed after the buffers.
+	 */
+	uf_buffer_virt_address = dmam_alloc_coherent(scic_to_dev(scic), size,
+							&uf_buffer_phys_address, GFP_KERNEL);
+	if (!uf_buffer_virt_address)
+		return -ENOMEM;
+
+	/*
+	 * Program the location of the UF header table into the SCU.
+	 * Notes:
+	 * - The address must align on a 64-byte boundary. Guaranteed to be
+	 *   on 64-byte boundary already 1KB boundary for unsolicited frames.
+	 * - Program unused header entries to overlap with the last
+	 *   unsolicited frame.  The silicon will never DMA to these unused
+	 *   headers, since we program the UF address table pointers to
+	 *   NULL.
+	 */
+	uf_control->headers.physical_address =
+				uf_buffer_phys_address +
+				used_uf_buffer_bytes -
+				unused_uf_header_bytes;
+
+	uf_control->headers.array =
+				uf_buffer_virt_address +
+				used_uf_buffer_bytes -
+				unused_uf_header_bytes;
+
+	/*
+	 * Program the location of the UF address table into the SCU.
+	 * Notes:
+	 * - The address must align on a 64-bit boundary. Guaranteed to be on 64
+	 *   byte boundary already due to above programming headers being on a
+	 *   64-bit boundary and headers are on a 64-bytes in size.
+	 */
+	uf_control->address_table.physical_address =
+				uf_buffer_phys_address +
+				used_uf_buffer_bytes +
+				used_uf_header_bytes;
+
+	uf_control->address_table.array =
+				uf_buffer_virt_address +
+				used_uf_buffer_bytes +
+				used_uf_header_bytes;
+
+	uf_control->get = 0;
+
+	/*
+	 * UF buffer requirements are:
+	 * - The last entry in the UF queue is not NULL.
+	 * - There is a power of 2 number of entries (NULL or not-NULL)
+	 *   programmed into the queue.
+	 * - Aligned on a 1KB boundary. */
+
+	/*
+	 * If the user provided less then the maximum amount of memory,
+	 * then be sure that we programm the first entries in the UF
+	 * address table to NULL. */
+	scic_sds_unsolicited_frame_control_construct_frames(
+		uf_control,
+		uf_buffer_phys_address,
+		uf_buffer_virt_address,
+		unused_uf_header_entries,
+		used_uf_header_entries
+		);
+
+	return 0;
+}
+
+/**
+ * This method returns the frame header for the specified frame index.
+ * @uf_control:
+ * @frame_index:
+ * @frame_header:
+ *
+ * enum sci_status
+ */
+enum sci_status scic_sds_unsolicited_frame_control_get_header(
+	struct scic_sds_unsolicited_frame_control *uf_control,
+	u32 frame_index,
+	void **frame_header)
+{
+	if (frame_index < uf_control->address_table.count) {
+		/*
+		 * Skip the first word in the frame since this is a controll word used
+		 * by the hardware. */
+		*frame_header = &uf_control->buffers.array[frame_index].header->data;
+
+		return SCI_SUCCESS;
+	}
+
+	return SCI_FAILURE_INVALID_PARAMETER_VALUE;
+}
+
+/**
+ * This method returns the frame buffer for the specified frame index.
+ * @uf_control:
+ * @frame_index:
+ * @frame_buffer:
+ *
+ * enum sci_status
+ */
+enum sci_status scic_sds_unsolicited_frame_control_get_buffer(
+	struct scic_sds_unsolicited_frame_control *uf_control,
+	u32 frame_index,
+	void **frame_buffer)
+{
+	if (frame_index < uf_control->address_table.count) {
+		*frame_buffer = uf_control->buffers.array[frame_index].buffer;
+
+		return SCI_SUCCESS;
+	}
+
+	return SCI_FAILURE_INVALID_PARAMETER_VALUE;
+}
+
+/**
+ * This method releases the frame once this is done the frame is available for
+ *    re-use by the hardware.  The data contained in the frame header and frame
+ *    buffer is no longer valid.
+ * @uf_control: This parameter specifies the UF control object
+ * @frame_index: This parameter specifies the frame index to attempt to release.
+ *
+ * This method returns an indication to the caller as to whether the
+ * unsolicited frame get pointer should be updated.
+ */
+bool scic_sds_unsolicited_frame_control_release_frame(
+	struct scic_sds_unsolicited_frame_control *uf_control,
+	u32 frame_index)
+{
+	u32 frame_get;
+	u32 frame_cycle;
+
+	frame_get   = uf_control->get & (uf_control->address_table.count - 1);
+	frame_cycle = uf_control->get & uf_control->address_table.count;
+
+	/*
+	 * In the event there are NULL entries in the UF table, we need to
+	 * advance the get pointer in order to find out if this frame should
+	 * be released (i.e. update the get pointer). */
+	while (((lower_32_bits(uf_control->address_table.array[frame_get])
+					== 0) &&
+		(upper_32_bits(uf_control->address_table.array[frame_get])
+					== 0)) &&
+	       (frame_get < uf_control->address_table.count))
+		frame_get++;
+
+	/*
+	 * The table has a NULL entry as it's last element.  This is
+	 * illegal. */
+	BUG_ON(frame_get >= uf_control->address_table.count);
+
+	if (frame_index < uf_control->address_table.count) {
+		uf_control->buffers.array[frame_index].state = UNSOLICITED_FRAME_RELEASED;
+
+		/*
+		 * The frame index is equal to the current get pointer so we
+		 * can now free up all of the frame entries that */
+		if (frame_get == frame_index) {
+			while (
+				uf_control->buffers.array[frame_get].state
+				== UNSOLICITED_FRAME_RELEASED
+				) {
+				uf_control->buffers.array[frame_get].state = UNSOLICITED_FRAME_EMPTY;
+
+				INCREMENT_QUEUE_GET(
+					frame_get,
+					frame_cycle,
+					uf_control->address_table.count - 1,
+					uf_control->address_table.count
+					);
+			}
+
+			uf_control->get =
+				(SCU_UFQGP_GEN_BIT(ENABLE_BIT) | frame_cycle | frame_get);
+
+			return true;
+		} else {
+			/*
+			 * Frames remain in use until we advance the get pointer
+			 * so there is nothing we can do here */
+		}
+	}
+
+	return false;
+}
+