diff options
Diffstat (limited to 'drivers/scsi/isci/unsolicited_frame_control.c')
-rw-r--r-- | drivers/scsi/isci/unsolicited_frame_control.c | 225 |
1 files changed, 225 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..e9e1e2abacb9 --- /dev/null +++ b/drivers/scsi/isci/unsolicited_frame_control.c @@ -0,0 +1,225 @@ +/* + * 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" + +int sci_unsolicited_frame_control_construct(struct isci_host *ihost) +{ + struct sci_unsolicited_frame_control *uf_control = &ihost->uf_control; + struct sci_unsolicited_frame *uf; + u32 buf_len, header_len, i; + dma_addr_t dma; + size_t size; + void *virt; + + /* + * Prepare all of the memory sizes for the UF headers, UF address + * table, and UF buffers themselves. + */ + buf_len = SCU_MAX_UNSOLICITED_FRAMES * SCU_UNSOLICITED_FRAME_BUFFER_SIZE; + header_len = SCU_MAX_UNSOLICITED_FRAMES * sizeof(struct scu_unsolicited_frame_header); + size = buf_len + header_len + SCU_MAX_UNSOLICITED_FRAMES * 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. + */ + virt = dmam_alloc_coherent(&ihost->pdev->dev, size, &dma, GFP_KERNEL); + if (!virt) + 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 = dma + buf_len; + uf_control->headers.array = virt + buf_len; + + /* + * 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 = dma + buf_len + header_len; + uf_control->address_table.array = virt + buf_len + header_len; + 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. */ + + /* + * Program the actual used UF buffers into the UF address table and + * the controller's array of UFs. + */ + for (i = 0; i < SCU_MAX_UNSOLICITED_FRAMES; i++) { + uf = &uf_control->buffers.array[i]; + + uf_control->address_table.array[i] = dma; + + uf->buffer = virt; + uf->header = &uf_control->headers.array[i]; + 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. + */ + virt += SCU_UNSOLICITED_FRAME_BUFFER_SIZE; + dma += SCU_UNSOLICITED_FRAME_BUFFER_SIZE; + } + + return 0; +} + +enum sci_status sci_unsolicited_frame_control_get_header(struct sci_unsolicited_frame_control *uf_control, + u32 frame_index, + void **frame_header) +{ + if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) { + /* 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; +} + +enum sci_status sci_unsolicited_frame_control_get_buffer(struct sci_unsolicited_frame_control *uf_control, + u32 frame_index, + void **frame_buffer) +{ + if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) { + *frame_buffer = uf_control->buffers.array[frame_index].buffer; + + return SCI_SUCCESS; + } + + return SCI_FAILURE_INVALID_PARAMETER_VALUE; +} + +bool sci_unsolicited_frame_control_release_frame(struct sci_unsolicited_frame_control *uf_control, + u32 frame_index) +{ + u32 frame_get; + u32 frame_cycle; + + frame_get = uf_control->get & (SCU_MAX_UNSOLICITED_FRAMES - 1); + frame_cycle = uf_control->get & SCU_MAX_UNSOLICITED_FRAMES; + + /* + * 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 < SCU_MAX_UNSOLICITED_FRAMES) + frame_get++; + + /* + * The table has a NULL entry as it's last element. This is + * illegal. + */ + BUG_ON(frame_get >= SCU_MAX_UNSOLICITED_FRAMES); + if (frame_index >= SCU_MAX_UNSOLICITED_FRAMES) + return false; + + uf_control->buffers.array[frame_index].state = UNSOLICITED_FRAME_RELEASED; + + if (frame_get != frame_index) { + /* + * Frames remain in use until we advance the get pointer + * so there is nothing we can do here + */ + return false; + } + + /* + * The frame index is equal to the current get pointer so we + * can now free up all of the frame entries that + */ + while (uf_control->buffers.array[frame_get].state == UNSOLICITED_FRAME_RELEASED) { + uf_control->buffers.array[frame_get].state = UNSOLICITED_FRAME_EMPTY; + + if (frame_get+1 == SCU_MAX_UNSOLICITED_FRAMES-1) { + frame_cycle ^= SCU_MAX_UNSOLICITED_FRAMES; + frame_get = 0; + } else + frame_get++; + } + + uf_control->get = SCU_UFQGP_GEN_BIT(ENABLE_BIT) | frame_cycle | frame_get; + + return true; +} |