1/***********************license start************************************
2 * Copyright (c) 2003-2017 Cavium, Inc.
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5 * License: one of 'Cavium License' or 'GNU General Public License Version 2'
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44 ***********************license end**************************************/
45
46#include "common.h"
47#include "zip_deflate.h"
48
49/**
50 * zip_cmd_queue_consumed - Calculates the space consumed in the command queue.
51 *
52 * @zip_dev: Pointer to zip device structure
53 * @queue:   Queue number
54 *
55 * Return: Bytes consumed in the command queue buffer.
56 */
57static inline u32 zip_cmd_queue_consumed(struct zip_device *zip_dev, int queue)
58{
59	return ((zip_dev->iq[queue].sw_head - zip_dev->iq[queue].sw_tail) *
60		sizeof(u64 *));
61}
62
63/**
64 * zip_load_instr - Submits the instruction into the ZIP command queue
65 * @instr:      Pointer to the instruction to be submitted
66 * @zip_dev:    Pointer to ZIP device structure to which the instruction is to
67 *              be submitted
68 *
69 * This function copies the ZIP instruction to the command queue and rings the
70 * doorbell to notify the engine of the instruction submission. The command
71 * queue is maintained in a circular fashion. When there is space for exactly
72 * one instruction in the queue, next chunk pointer of the queue is made to
73 * point to the head of the queue, thus maintaining a circular queue.
74 *
75 * Return: Queue number to which the instruction was submitted
76 */
77u32 zip_load_instr(union zip_inst_s *instr,
78		   struct zip_device *zip_dev)
79{
80	union zip_quex_doorbell dbell;
81	u32 queue = 0;
82	u32 consumed = 0;
83	u64 *ncb_ptr = NULL;
84	union zip_nptr_s ncp;
85
86	/*
87	 * Distribute the instructions between the enabled queues based on
88	 * the CPU id.
89	 */
90	if (raw_smp_processor_id() % 2 == 0)
91		queue = 0;
92	else
93		queue = 1;
94
95	zip_dbg("CPU Core: %d Queue number:%d", raw_smp_processor_id(), queue);
96
97	/* Take cmd buffer lock */
98	spin_lock(&zip_dev->iq[queue].lock);
99
100	/*
101	 * Command Queue implementation
102	 * 1. If there is place for new instructions, push the cmd at sw_head.
103	 * 2. If there is place for exactly one instruction, push the new cmd
104	 *    at the sw_head. Make sw_head point to the sw_tail to make it
105	 *    circular. Write sw_head's physical address to the "Next-Chunk
106	 *    Buffer Ptr" to make it cmd_hw_tail.
107	 * 3. Ring the door bell.
108	 */
109	zip_dbg("sw_head : %lx", zip_dev->iq[queue].sw_head);
110	zip_dbg("sw_tail : %lx", zip_dev->iq[queue].sw_tail);
111
112	consumed = zip_cmd_queue_consumed(zip_dev, queue);
113	/* Check if there is space to push just one cmd */
114	if ((consumed + 128) == (ZIP_CMD_QBUF_SIZE - 8)) {
115		zip_dbg("Cmd queue space available for single command");
116		/* Space for one cmd, pust it and make it circular queue */
117		memcpy((u8 *)zip_dev->iq[queue].sw_head, (u8 *)instr,
118		       sizeof(union zip_inst_s));
119		zip_dev->iq[queue].sw_head += 16; /* 16 64_bit words = 128B */
120
121		/* Now, point the "Next-Chunk Buffer Ptr" to sw_head */
122		ncb_ptr = zip_dev->iq[queue].sw_head;
123
124		zip_dbg("ncb addr :0x%lx sw_head addr :0x%lx",
125			ncb_ptr, zip_dev->iq[queue].sw_head - 16);
126
127		/* Using Circular command queue */
128		zip_dev->iq[queue].sw_head = zip_dev->iq[queue].sw_tail;
129		/* Mark this buffer for free */
130		zip_dev->iq[queue].free_flag = 1;
131
132		/* Write new chunk buffer address at "Next-Chunk Buffer Ptr" */
133		ncp.u_reg64 = 0ull;
134		ncp.s.addr = __pa(zip_dev->iq[queue].sw_head);
135		*ncb_ptr = ncp.u_reg64;
136		zip_dbg("*ncb_ptr :0x%lx sw_head[phys] :0x%lx",
137			*ncb_ptr, __pa(zip_dev->iq[queue].sw_head));
138
139		zip_dev->iq[queue].pend_cnt++;
140
141	} else {
142		zip_dbg("Enough space is available for commands");
143		/* Push this cmd to cmd queue buffer */
144		memcpy((u8 *)zip_dev->iq[queue].sw_head, (u8 *)instr,
145		       sizeof(union zip_inst_s));
146		zip_dev->iq[queue].sw_head += 16; /* 16 64_bit words = 128B */
147
148		zip_dev->iq[queue].pend_cnt++;
149	}
150	zip_dbg("sw_head :0x%lx sw_tail :0x%lx hw_tail :0x%lx",
151		zip_dev->iq[queue].sw_head, zip_dev->iq[queue].sw_tail,
152		zip_dev->iq[queue].hw_tail);
153
154	zip_dbg(" Pushed the new cmd : pend_cnt : %d",
155		zip_dev->iq[queue].pend_cnt);
156
157	/* Ring the doorbell */
158	dbell.u_reg64     = 0ull;
159	dbell.s.dbell_cnt = 1;
160	zip_reg_write(dbell.u_reg64,
161		      (zip_dev->reg_base + ZIP_QUEX_DOORBELL(queue)));
162
163	/* Unlock cmd buffer lock */
164	spin_unlock(&zip_dev->iq[queue].lock);
165
166	return queue;
167}
168
169/**
170 * zip_update_cmd_bufs - Updates the queue statistics after posting the
171 *                       instruction
172 * @zip_dev: Pointer to zip device structure
173 * @queue:   Queue number
174 */
175void zip_update_cmd_bufs(struct zip_device *zip_dev, u32 queue)
176{
177	/* Take cmd buffer lock */
178	spin_lock(&zip_dev->iq[queue].lock);
179
180	/* Check if the previous buffer can be freed */
181	if (zip_dev->iq[queue].free_flag == 1) {
182		zip_dbg("Free flag. Free cmd buffer, adjust sw head and tail");
183		/* Reset the free flag */
184		zip_dev->iq[queue].free_flag = 0;
185
186		/* Point the hw_tail to start of the new chunk buffer */
187		zip_dev->iq[queue].hw_tail = zip_dev->iq[queue].sw_head;
188	} else {
189		zip_dbg("Free flag not set. increment hw tail");
190		zip_dev->iq[queue].hw_tail += 16; /* 16 64_bit words = 128B */
191	}
192
193	zip_dev->iq[queue].done_cnt++;
194	zip_dev->iq[queue].pend_cnt--;
195
196	zip_dbg("sw_head :0x%lx sw_tail :0x%lx hw_tail :0x%lx",
197		zip_dev->iq[queue].sw_head, zip_dev->iq[queue].sw_tail,
198		zip_dev->iq[queue].hw_tail);
199	zip_dbg(" Got CC : pend_cnt : %d\n", zip_dev->iq[queue].pend_cnt);
200
201	spin_unlock(&zip_dev->iq[queue].lock);
202}
203