--- /dev/null
+/***********************license start***************
+ * Author: Cavium Networks
+ *
+ * Contact: support@caviumnetworks.com
+ * This file is part of the OCTEON SDK
+ *
+ * Copyright (c) 2003-2008 Cavium Networks
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, Version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
+ * NONINFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this file; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * or visit http://www.gnu.org/licenses/.
+ *
+ * This file may also be available under a different license from Cavium.
+ * Contact Cavium Networks for more information
+ ***********************license end**************************************/
+
+/*
+ *
+ * Support functions for managing command queues used for
+ * various hardware blocks.
+ *
+ * The common command queue infrastructure abstracts out the
+ * software necessary for adding to Octeon's chained queue
+ * structures. These structures are used for commands to the
+ * PKO, ZIP, DFA, RAID, and DMA engine blocks. Although each
+ * hardware unit takes commands and CSRs of different types,
+ * they all use basic linked command buffers to store the
+ * pending request. In general, users of the CVMX API don't
+ * call cvmx-cmd-queue functions directly. Instead the hardware
+ * unit specific wrapper should be used. The wrappers perform
+ * unit specific validation and CSR writes to submit the
+ * commands.
+ *
+ * Even though most software will never directly interact with
+ * cvmx-cmd-queue, knowledge of its internal working can help
+ * in diagnosing performance problems and help with debugging.
+ *
+ * Command queue pointers are stored in a global named block
+ * called "cvmx_cmd_queues". Except for the PKO queues, each
+ * hardware queue is stored in its own cache line to reduce SMP
+ * contention on spin locks. The PKO queues are stored such that
+ * every 16th queue is next to each other in memory. This scheme
+ * allows for queues being in separate cache lines when there
+ * are low number of queues per port. With 16 queues per port,
+ * the first queue for each port is in the same cache area. The
+ * second queues for each port are in another area, etc. This
+ * allows software to implement very efficient lockless PKO with
+ * 16 queues per port using a minimum of cache lines per core.
+ * All queues for a given core will be isolated in the same
+ * cache area.
+ *
+ * In addition to the memory pointer layout, cvmx-cmd-queue
+ * provides an optimized fair ll/sc locking mechanism for the
+ * queues. The lock uses a "ticket / now serving" model to
+ * maintain fair order on contended locks. In addition, it uses
+ * predicted locking time to limit cache contention. When a core
+ * know it must wait in line for a lock, it spins on the
+ * internal cycle counter to completely eliminate any causes of
+ * bus traffic.
+ *
+ */
+
+#ifndef __CVMX_CMD_QUEUE_H__
+#define __CVMX_CMD_QUEUE_H__
+
+#include <linux/prefetch.h>
+
+#include "cvmx-fpa.h"
+/**
+ * By default we disable the max depth support. Most programs
+ * don't use it and it slows down the command queue processing
+ * significantly.
+ */
+#ifndef CVMX_CMD_QUEUE_ENABLE_MAX_DEPTH
+#define CVMX_CMD_QUEUE_ENABLE_MAX_DEPTH 0
+#endif
+
+/**
+ * Enumeration representing all hardware blocks that use command
+ * queues. Each hardware block has up to 65536 sub identifiers for
+ * multiple command queues. Not all chips support all hardware
+ * units.
+ */
+typedef enum {
+ CVMX_CMD_QUEUE_PKO_BASE = 0x00000,
+
+#define CVMX_CMD_QUEUE_PKO(queue) \
+ ((cvmx_cmd_queue_id_t)(CVMX_CMD_QUEUE_PKO_BASE + (0xffff&(queue))))
+
+ CVMX_CMD_QUEUE_ZIP = 0x10000,
+ CVMX_CMD_QUEUE_DFA = 0x20000,
+ CVMX_CMD_QUEUE_RAID = 0x30000,
+ CVMX_CMD_QUEUE_DMA_BASE = 0x40000,
+
+#define CVMX_CMD_QUEUE_DMA(queue) \
+ ((cvmx_cmd_queue_id_t)(CVMX_CMD_QUEUE_DMA_BASE + (0xffff&(queue))))
+
+ CVMX_CMD_QUEUE_END = 0x50000,
+} cvmx_cmd_queue_id_t;
+
+/**
+ * Command write operations can fail if the command queue needs
+ * a new buffer and the associated FPA pool is empty. It can also
+ * fail if the number of queued command words reaches the maximum
+ * set at initialization.
+ */
+typedef enum {
+ CVMX_CMD_QUEUE_SUCCESS = 0,
+ CVMX_CMD_QUEUE_NO_MEMORY = -1,
+ CVMX_CMD_QUEUE_FULL = -2,
+ CVMX_CMD_QUEUE_INVALID_PARAM = -3,
+ CVMX_CMD_QUEUE_ALREADY_SETUP = -4,
+} cvmx_cmd_queue_result_t;
+
+typedef struct {
+ /* You have lock when this is your ticket */
+ uint8_t now_serving;
+ uint64_t unused1:24;
+ /* Maximum outstanding command words */
+ uint32_t max_depth;
+ /* FPA pool buffers come from */
+ uint64_t fpa_pool:3;
+ /* Top of command buffer pointer shifted 7 */
+ uint64_t base_ptr_div128:29;
+ uint64_t unused2:6;
+ /* FPA buffer size in 64bit words minus 1 */
+ uint64_t pool_size_m1:13;
+ /* Number of commands already used in buffer */
+ uint64_t index:13;
+} __cvmx_cmd_queue_state_t;
+
+/**
+ * This structure contains the global state of all command queues.
+ * It is stored in a bootmem named block and shared by all
+ * applications running on Octeon. Tickets are stored in a differnet
+ * cahce line that queue information to reduce the contention on the
+ * ll/sc used to get a ticket. If this is not the case, the update
+ * of queue state causes the ll/sc to fail quite often.
+ */
+typedef struct {
+ uint64_t ticket[(CVMX_CMD_QUEUE_END >> 16) * 256];
+ __cvmx_cmd_queue_state_t state[(CVMX_CMD_QUEUE_END >> 16) * 256];
+} __cvmx_cmd_queue_all_state_t;
+
+/**
+ * Initialize a command queue for use. The initial FPA buffer is
+ * allocated and the hardware unit is configured to point to the
+ * new command queue.
+ *
+ * @queue_id: Hardware command queue to initialize.
+ * @max_depth: Maximum outstanding commands that can be queued.
+ * @fpa_pool: FPA pool the command queues should come from.
+ * @pool_size: Size of each buffer in the FPA pool (bytes)
+ *
+ * Returns CVMX_CMD_QUEUE_SUCCESS or a failure code
+ */
+cvmx_cmd_queue_result_t cvmx_cmd_queue_initialize(cvmx_cmd_queue_id_t queue_id,
+ int max_depth, int fpa_pool,
+ int pool_size);
+
+/**
+ * Shutdown a queue a free it's command buffers to the FPA. The
+ * hardware connected to the queue must be stopped before this
+ * function is called.
+ *
+ * @queue_id: Queue to shutdown
+ *
+ * Returns CVMX_CMD_QUEUE_SUCCESS or a failure code
+ */
+cvmx_cmd_queue_result_t cvmx_cmd_queue_shutdown(cvmx_cmd_queue_id_t queue_id);
+
+/**
+ * Return the number of command words pending in the queue. This
+ * function may be relatively slow for some hardware units.
+ *
+ * @queue_id: Hardware command queue to query
+ *
+ * Returns Number of outstanding commands
+ */
+int cvmx_cmd_queue_length(cvmx_cmd_queue_id_t queue_id);
+
+/**
+ * Return the command buffer to be written to. The purpose of this
+ * function is to allow CVMX routine access t othe low level buffer
+ * for initial hardware setup. User applications should not call this
+ * function directly.
+ *
+ * @queue_id: Command queue to query
+ *
+ * Returns Command buffer or NULL on failure
+ */
+void *cvmx_cmd_queue_buffer(cvmx_cmd_queue_id_t queue_id);
+
+/**
+ * Get the index into the state arrays for the supplied queue id.
+ *
+ * @queue_id: Queue ID to get an index for
+ *
+ * Returns Index into the state arrays
+ */
+static inline int __cvmx_cmd_queue_get_index(cvmx_cmd_queue_id_t queue_id)
+{
+ /*
+ * Warning: This code currently only works with devices that
+ * have 256 queues or less. Devices with more than 16 queues
+ * are laid out in memory to allow cores quick access to
+ * every 16th queue. This reduces cache thrashing when you are
+ * running 16 queues per port to support lockless operation.
+ */
+ int unit = queue_id >> 16;
+ int q = (queue_id >> 4) & 0xf;
+ int core = queue_id & 0xf;
+ return unit * 256 + core * 16 + q;
+}
+
+/**
+ * Lock the supplied queue so nobody else is updating it at the same
+ * time as us.
+ *
+ * @queue_id: Queue ID to lock
+ * @qptr: Pointer to the queue's global state
+ */
+static inline void __cvmx_cmd_queue_lock(cvmx_cmd_queue_id_t queue_id,
+ __cvmx_cmd_queue_state_t *qptr)
+{
+ extern __cvmx_cmd_queue_all_state_t
+ *__cvmx_cmd_queue_state_ptr;
+ int tmp;
+ int my_ticket;
+ prefetch(qptr);
+ asm volatile (
+ ".set push\n"
+ ".set noreorder\n"
+ "1:\n"
+ /* Atomic add one to ticket_ptr */
+ "ll %[my_ticket], %[ticket_ptr]\n"
+ /* and store the original value */
+ "li %[ticket], 1\n"
+ /* in my_ticket */
+ "baddu %[ticket], %[my_ticket]\n"
+ "sc %[ticket], %[ticket_ptr]\n"
+ "beqz %[ticket], 1b\n"
+ " nop\n"
+ /* Load the current now_serving ticket */
+ "lbu %[ticket], %[now_serving]\n"
+ "2:\n"
+ /* Jump out if now_serving == my_ticket */
+ "beq %[ticket], %[my_ticket], 4f\n"
+ /* Find out how many tickets are in front of me */
+ " subu %[ticket], %[my_ticket], %[ticket]\n"
+ /* Use tickets in front of me minus one to delay */
+ "subu %[ticket], 1\n"
+ /* Delay will be ((tickets in front)-1)*32 loops */
+ "cins %[ticket], %[ticket], 5, 7\n"
+ "3:\n"
+ /* Loop here until our ticket might be up */
+ "bnez %[ticket], 3b\n"
+ " subu %[ticket], 1\n"
+ /* Jump back up to check out ticket again */
+ "b 2b\n"
+ /* Load the current now_serving ticket */
+ " lbu %[ticket], %[now_serving]\n"
+ "4:\n"
+ ".set pop\n" :
+ [ticket_ptr] "=m"(__cvmx_cmd_queue_state_ptr->ticket[__cvmx_cmd_queue_get_index(queue_id)]),
+ [now_serving] "=m"(qptr->now_serving), [ticket] "=r"(tmp),
+ [my_ticket] "=r"(my_ticket)
+ );
+}
+
+/**
+ * Unlock the queue, flushing all writes.
+ *
+ * @qptr: Queue to unlock
+ */
+static inline void __cvmx_cmd_queue_unlock(__cvmx_cmd_queue_state_t *qptr)
+{
+ qptr->now_serving++;
+ CVMX_SYNCWS;
+}
+
+/**
+ * Get the queue state structure for the given queue id
+ *
+ * @queue_id: Queue id to get
+ *
+ * Returns Queue structure or NULL on failure
+ */
+static inline __cvmx_cmd_queue_state_t
+ *__cvmx_cmd_queue_get_state(cvmx_cmd_queue_id_t queue_id)
+{
+ extern __cvmx_cmd_queue_all_state_t
+ *__cvmx_cmd_queue_state_ptr;
+ return &__cvmx_cmd_queue_state_ptr->
+ state[__cvmx_cmd_queue_get_index(queue_id)];
+}
+
+/**
+ * Write an arbitrary number of command words to a command queue.
+ * This is a generic function; the fixed number of command word
+ * functions yield higher performance.
+ *
+ * @queue_id: Hardware command queue to write to
+ * @use_locking:
+ * Use internal locking to ensure exclusive access for queue
+ * updates. If you don't use this locking you must ensure
+ * exclusivity some other way. Locking is strongly recommended.
+ * @cmd_count: Number of command words to write
+ * @cmds: Array of commands to write
+ *
+ * Returns CVMX_CMD_QUEUE_SUCCESS or a failure code
+ */
+static inline cvmx_cmd_queue_result_t cvmx_cmd_queue_write(cvmx_cmd_queue_id_t
+ queue_id,
+ int use_locking,
+ int cmd_count,
+ uint64_t *cmds)
+{
+ __cvmx_cmd_queue_state_t *qptr = __cvmx_cmd_queue_get_state(queue_id);
+
+ /* Make sure nobody else is updating the same queue */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_lock(queue_id, qptr);
+
+ /*
+ * If a max queue length was specified then make sure we don't
+ * exceed it. If any part of the command would be below the
+ * limit we allow it.
+ */
+ if (CVMX_CMD_QUEUE_ENABLE_MAX_DEPTH && unlikely(qptr->max_depth)) {
+ if (unlikely
+ (cvmx_cmd_queue_length(queue_id) > (int)qptr->max_depth)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_FULL;
+ }
+ }
+
+ /*
+ * Normally there is plenty of room in the current buffer for
+ * the command.
+ */
+ if (likely(qptr->index + cmd_count < qptr->pool_size_m1)) {
+ uint64_t *ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ ptr += qptr->index;
+ qptr->index += cmd_count;
+ while (cmd_count--)
+ *ptr++ = *cmds++;
+ } else {
+ uint64_t *ptr;
+ int count;
+ /*
+ * We need a new command buffer. Fail if there isn't
+ * one available.
+ */
+ uint64_t *new_buffer =
+ (uint64_t *) cvmx_fpa_alloc(qptr->fpa_pool);
+ if (unlikely(new_buffer == NULL)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_NO_MEMORY;
+ }
+ ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ /*
+ * Figure out how many command words will fit in this
+ * buffer. One location will be needed for the next
+ * buffer pointer.
+ */
+ count = qptr->pool_size_m1 - qptr->index;
+ ptr += qptr->index;
+ cmd_count -= count;
+ while (count--)
+ *ptr++ = *cmds++;
+ *ptr = cvmx_ptr_to_phys(new_buffer);
+ /*
+ * The current buffer is full and has a link to the
+ * next buffer. Time to write the rest of the commands
+ * into the new buffer.
+ */
+ qptr->base_ptr_div128 = *ptr >> 7;
+ qptr->index = cmd_count;
+ ptr = new_buffer;
+ while (cmd_count--)
+ *ptr++ = *cmds++;
+ }
+
+ /* All updates are complete. Release the lock and return */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_SUCCESS;
+}
+
+/**
+ * Simple function to write two command words to a command
+ * queue.
+ *
+ * @queue_id: Hardware command queue to write to
+ * @use_locking:
+ * Use internal locking to ensure exclusive access for queue
+ * updates. If you don't use this locking you must ensure
+ * exclusivity some other way. Locking is strongly recommended.
+ * @cmd1: Command
+ * @cmd2: Command
+ *
+ * Returns CVMX_CMD_QUEUE_SUCCESS or a failure code
+ */
+static inline cvmx_cmd_queue_result_t cvmx_cmd_queue_write2(cvmx_cmd_queue_id_t
+ queue_id,
+ int use_locking,
+ uint64_t cmd1,
+ uint64_t cmd2)
+{
+ __cvmx_cmd_queue_state_t *qptr = __cvmx_cmd_queue_get_state(queue_id);
+
+ /* Make sure nobody else is updating the same queue */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_lock(queue_id, qptr);
+
+ /*
+ * If a max queue length was specified then make sure we don't
+ * exceed it. If any part of the command would be below the
+ * limit we allow it.
+ */
+ if (CVMX_CMD_QUEUE_ENABLE_MAX_DEPTH && unlikely(qptr->max_depth)) {
+ if (unlikely
+ (cvmx_cmd_queue_length(queue_id) > (int)qptr->max_depth)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_FULL;
+ }
+ }
+
+ /*
+ * Normally there is plenty of room in the current buffer for
+ * the command.
+ */
+ if (likely(qptr->index + 2 < qptr->pool_size_m1)) {
+ uint64_t *ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ ptr += qptr->index;
+ qptr->index += 2;
+ ptr[0] = cmd1;
+ ptr[1] = cmd2;
+ } else {
+ uint64_t *ptr;
+ /*
+ * Figure out how many command words will fit in this
+ * buffer. One location will be needed for the next
+ * buffer pointer.
+ */
+ int count = qptr->pool_size_m1 - qptr->index;
+ /*
+ * We need a new command buffer. Fail if there isn't
+ * one available.
+ */
+ uint64_t *new_buffer =
+ (uint64_t *) cvmx_fpa_alloc(qptr->fpa_pool);
+ if (unlikely(new_buffer == NULL)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_NO_MEMORY;
+ }
+ count--;
+ ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ ptr += qptr->index;
+ *ptr++ = cmd1;
+ if (likely(count))
+ *ptr++ = cmd2;
+ *ptr = cvmx_ptr_to_phys(new_buffer);
+ /*
+ * The current buffer is full and has a link to the
+ * next buffer. Time to write the rest of the commands
+ * into the new buffer.
+ */
+ qptr->base_ptr_div128 = *ptr >> 7;
+ qptr->index = 0;
+ if (unlikely(count == 0)) {
+ qptr->index = 1;
+ new_buffer[0] = cmd2;
+ }
+ }
+
+ /* All updates are complete. Release the lock and return */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_SUCCESS;
+}
+
+/**
+ * Simple function to write three command words to a command
+ * queue.
+ *
+ * @queue_id: Hardware command queue to write to
+ * @use_locking:
+ * Use internal locking to ensure exclusive access for queue
+ * updates. If you don't use this locking you must ensure
+ * exclusivity some other way. Locking is strongly recommended.
+ * @cmd1: Command
+ * @cmd2: Command
+ * @cmd3: Command
+ *
+ * Returns CVMX_CMD_QUEUE_SUCCESS or a failure code
+ */
+static inline cvmx_cmd_queue_result_t cvmx_cmd_queue_write3(cvmx_cmd_queue_id_t
+ queue_id,
+ int use_locking,
+ uint64_t cmd1,
+ uint64_t cmd2,
+ uint64_t cmd3)
+{
+ __cvmx_cmd_queue_state_t *qptr = __cvmx_cmd_queue_get_state(queue_id);
+
+ /* Make sure nobody else is updating the same queue */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_lock(queue_id, qptr);
+
+ /*
+ * If a max queue length was specified then make sure we don't
+ * exceed it. If any part of the command would be below the
+ * limit we allow it.
+ */
+ if (CVMX_CMD_QUEUE_ENABLE_MAX_DEPTH && unlikely(qptr->max_depth)) {
+ if (unlikely
+ (cvmx_cmd_queue_length(queue_id) > (int)qptr->max_depth)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_FULL;
+ }
+ }
+
+ /*
+ * Normally there is plenty of room in the current buffer for
+ * the command.
+ */
+ if (likely(qptr->index + 3 < qptr->pool_size_m1)) {
+ uint64_t *ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ ptr += qptr->index;
+ qptr->index += 3;
+ ptr[0] = cmd1;
+ ptr[1] = cmd2;
+ ptr[2] = cmd3;
+ } else {
+ uint64_t *ptr;
+ /*
+ * Figure out how many command words will fit in this
+ * buffer. One location will be needed for the next
+ * buffer pointer
+ */
+ int count = qptr->pool_size_m1 - qptr->index;
+ /*
+ * We need a new command buffer. Fail if there isn't
+ * one available
+ */
+ uint64_t *new_buffer =
+ (uint64_t *) cvmx_fpa_alloc(qptr->fpa_pool);
+ if (unlikely(new_buffer == NULL)) {
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_NO_MEMORY;
+ }
+ count--;
+ ptr =
+ (uint64_t *) cvmx_phys_to_ptr((uint64_t) qptr->
+ base_ptr_div128 << 7);
+ ptr += qptr->index;
+ *ptr++ = cmd1;
+ if (count) {
+ *ptr++ = cmd2;
+ if (count > 1)
+ *ptr++ = cmd3;
+ }
+ *ptr = cvmx_ptr_to_phys(new_buffer);
+ /*
+ * The current buffer is full and has a link to the
+ * next buffer. Time to write the rest of the commands
+ * into the new buffer.
+ */
+ qptr->base_ptr_div128 = *ptr >> 7;
+ qptr->index = 0;
+ ptr = new_buffer;
+ if (count == 0) {
+ *ptr++ = cmd2;
+ qptr->index++;
+ }
+ if (count < 2) {
+ *ptr++ = cmd3;
+ qptr->index++;
+ }
+ }
+
+ /* All updates are complete. Release the lock and return */
+ if (likely(use_locking))
+ __cvmx_cmd_queue_unlock(qptr);
+ return CVMX_CMD_QUEUE_SUCCESS;
+}
+
+#endif /* __CVMX_CMD_QUEUE_H__ */
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