1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * sl3516-ce.h - hardware cryptographic offloader for cortina/gemini SoC
4  *
5  * Copyright (C) 2021 Corentin LABBE <clabbe@baylibre.com>
6  *
7  * General notes on this driver:
8  * Called either Crypto Acceleration Engine Module, Security Acceleration Engine
9  * or IPSEC module in the datasheet, it will be called Crypto Engine for short
10  * in this driver.
11  * The CE was designed to handle IPSEC and wifi(TKIP WEP) protocol.
12  * It can handle AES, DES, 3DES, MD5, WEP, TKIP, SHA1, HMAC(MD5), HMAC(SHA1),
13  * Michael cipher/digest suites.
14  * It acts the same as a network hw, with both RX and TX chained descriptors.
15  */
16 #include <crypto/aes.h>
17 #include <crypto/engine.h>
18 #include <crypto/scatterwalk.h>
19 #include <crypto/skcipher.h>
20 #include <linux/debugfs.h>
21 #include <linux/hw_random.h>
22 
23 #define TQ0_TYPE_DATA 0
24 #define TQ0_TYPE_CTRL BIT(0)
25 #define TQ1_CIPHER BIT(1)
26 #define TQ2_AUTH BIT(2)
27 #define TQ3_IV BIT(3)
28 #define TQ4_KEY0 BIT(4)
29 #define TQ5_KEY4 BIT(5)
30 #define TQ6_KEY6 BIT(6)
31 #define TQ7_AKEY0 BIT(7)
32 #define TQ8_AKEY2 BIT(8)
33 #define TQ9_AKEY2 BIT(9)
34 
35 #define ECB_AES       0x2
36 
37 #define DESC_LAST 0x01
38 #define DESC_FIRST 0x02
39 
40 #define IPSEC_ID		0x0000
41 #define IPSEC_STATUS_REG	0x00a8
42 #define IPSEC_RAND_NUM_REG	0x00ac
43 #define IPSEC_DMA_DEVICE_ID	0xff00
44 #define IPSEC_DMA_STATUS	0xff04
45 #define IPSEC_TXDMA_CTRL	0xff08
46 #define IPSEC_TXDMA_FIRST_DESC	0xff0c
47 #define IPSEC_TXDMA_CURR_DESC	0xff10
48 #define IPSEC_RXDMA_CTRL	0xff14
49 #define IPSEC_RXDMA_FIRST_DESC	0xff18
50 #define IPSEC_RXDMA_CURR_DESC	0xff1c
51 #define IPSEC_TXDMA_BUF_ADDR	0xff28
52 #define IPSEC_RXDMA_BUF_ADDR	0xff38
53 #define IPSEC_RXDMA_BUF_SIZE	0xff30
54 
55 #define CE_ENCRYPTION		0x01
56 #define CE_DECRYPTION		0x03
57 
58 #define MAXDESC 6
59 
60 #define DMA_STATUS_RS_EOFI	BIT(22)
61 #define DMA_STATUS_RS_PERR	BIT(24)
62 #define DMA_STATUS_RS_DERR	BIT(25)
63 #define DMA_STATUS_TS_EOFI	BIT(27)
64 #define DMA_STATUS_TS_PERR	BIT(29)
65 #define DMA_STATUS_TS_DERR	BIT(30)
66 
67 #define TXDMA_CTRL_START BIT(31)
68 #define TXDMA_CTRL_CONTINUE BIT(30)
69 #define TXDMA_CTRL_CHAIN_MODE BIT(29)
70 /* the burst value is not documented in the datasheet */
71 #define TXDMA_CTRL_BURST_UNK BIT(22)
72 #define TXDMA_CTRL_INT_FAIL BIT(17)
73 #define TXDMA_CTRL_INT_PERR BIT(16)
74 
75 #define RXDMA_CTRL_START BIT(31)
76 #define RXDMA_CTRL_CONTINUE BIT(30)
77 #define RXDMA_CTRL_CHAIN_MODE BIT(29)
78 /* the burst value is not documented in the datasheet */
79 #define RXDMA_CTRL_BURST_UNK BIT(22)
80 #define RXDMA_CTRL_INT_FINISH BIT(18)
81 #define RXDMA_CTRL_INT_FAIL BIT(17)
82 #define RXDMA_CTRL_INT_PERR BIT(16)
83 #define RXDMA_CTRL_INT_EOD BIT(15)
84 #define RXDMA_CTRL_INT_EOF BIT(14)
85 
86 #define CE_CPU 0
87 #define CE_DMA 1
88 
89 /*
90  * struct sl3516_ce_descriptor - descriptor for CE operations
91  * @frame_ctrl:		Information for the current descriptor
92  * @flag_status:	For send packet, describe flag of operations.
93  * @buf_adr:		pointer to a send/recv buffer for data packet
94  * @next_desc:		control linking to other descriptors
95  */
96 struct descriptor {
97 	union {
98 		u32 raw;
99 		/*
100 		 * struct desc_frame_ctrl - Information for the current descriptor
101 		 * @buffer_size:	the size of buffer at buf_adr
102 		 * @desc_count:		Upon completion of a DMA operation, DMA
103 		 *			write the number of descriptors used
104 		 *			for the current frame
105 		 * @checksum:		unknown
106 		 * @authcomp:		unknown
107 		 * @perr:		Protocol error during processing this descriptor
108 		 * @derr:		Data error during processing this descriptor
109 		 * @own:		0 if owned by CPU, 1 for DMA
110 		 */
111 		struct desc_frame_ctrl {
112 			u32 buffer_size	:16;
113 			u32 desc_count	:6;
114 			u32 checksum	:6;
115 			u32 authcomp	:1;
116 			u32 perr	:1;
117 			u32 derr	:1;
118 			u32 own		:1;
119 		} bits;
120 	} frame_ctrl;
121 
122 	union {
123 		u32 raw;
124 		/*
125 		 * struct desc_flag_status - flag for this descriptor
126 		 * @tqflag:	list of flag describing the type of operation
127 		 *		to be performed.
128 		 */
129 		struct desc_tx_flag_status {
130 			u32 tqflag	:10;
131 			u32 unused	:22;
132 		} tx_flag;
133 	} flag_status;
134 
135 	u32 buf_adr;
136 
137 	union {
138 		u32 next_descriptor;
139 		/*
140 		 * struct desc_next - describe chaining of descriptors
141 		 * @sof_eof:	does the descriptor is first (0x11),
142 		 *		the last (0x01), middle of a chan (0x00)
143 		 *		or the only one (0x11)
144 		 * @dec:	AHB bus address increase (0), decrease (1)
145 		 * @eofie:	End of frame interrupt enable
146 		 * @ndar:	Next descriptor address
147 		 */
148 		struct desc_next {
149 			u32 sof_eof	:2;
150 			u32 dec		:1;
151 			u32 eofie	:1;
152 			u32 ndar	:28;
153 		} bits;
154 	} next_desc;
155 };
156 
157 /*
158  * struct control - The value of this register is used to set the
159  *			operation mode of the IPSec Module.
160  * @process_id:		Used to identify the process. The number will be copied
161  *			to the descriptor status of the received packet.
162  * @auth_check_len:	Number of 32-bit words to be checked or appended by the
163  *			authentication module
164  * @auth_algorithm:
165  * @auth_mode:		0:append 1:Check Authentication Result
166  * @fcs_stream_copy:	0:enable 1:disable authentication stream copy
167  * @mix_key_sel:	0:use rCipherKey0-3  1:use Key Mixer
168  * @aesnk:		AES Key Size
169  * @cipher_algorithm:	choice of CBC/ECE and AES/DES/3DES
170  * @op_mode:		Operation Mode for the IPSec Module
171  */
172 struct pkt_control_header {
173 	u32 process_id		:8;
174 	u32 auth_check_len	:3;
175 	u32 un1			:1;
176 	u32 auth_algorithm	:3;
177 	u32 auth_mode		:1;
178 	u32 fcs_stream_copy	:1;
179 	u32 un2			:2;
180 	u32 mix_key_sel		:1;
181 	u32 aesnk		:4;
182 	u32 cipher_algorithm	:3;
183 	u32 un3			:1;
184 	u32 op_mode		:4;
185 };
186 
187 struct pkt_control_cipher {
188 	u32 algorithm_len	:16;
189 	u32 header_len		:16;
190 };
191 
192 /*
193  * struct pkt_control_ecb - control packet for ECB
194  */
195 struct pkt_control_ecb {
196 	struct pkt_control_header control;
197 	struct pkt_control_cipher cipher;
198 	unsigned char key[AES_MAX_KEY_SIZE];
199 };
200 
201 /*
202  * struct sl3516_ce_dev - main container for all this driver information
203  * @base:	base address
204  * @clks:	clocks used
205  * @reset:	pointer to reset controller
206  * @dev:	the platform device
207  * @engine:	ptr to the crypto/crypto_engine
208  * @complete:	completion for the current task on this flow
209  * @status:	set to 1 by interrupt if task is done
210  * @dtx:	base DMA address for TX descriptors
211  * @tx		base address of TX descriptors
212  * @drx:	base DMA address for RX descriptors
213  * @rx		base address of RX descriptors
214  * @ctx		current used TX descriptor
215  * @crx		current used RX descriptor
216  * @trng	hw_random structure for RNG
217  * @hwrng_stat_req	number of HWRNG requests
218  * @hwrng_stat_bytes	total number of bytes generated by RNG
219  * @stat_irq	number of IRQ handled by CE
220  * @stat_irq_tx	number of TX IRQ handled by CE
221  * @stat_irq_rx	number of RX IRQ handled by CE
222  * @stat_req	number of requests handled by CE
223  * @fallbak_sg_count_tx		number of fallback due to destination SG count
224  * @fallbak_sg_count_rx		number of fallback due to source SG count
225  * @fallbak_not_same_len	number of fallback due to difference in SG length
226  * @dbgfs_dir:	Debugfs dentry for statistic directory
227  * @dbgfs_stats: Debugfs dentry for statistic counters
228  */
229 struct sl3516_ce_dev {
230 	void __iomem *base;
231 	struct clk *clks;
232 	struct reset_control *reset;
233 	struct device *dev;
234 	struct crypto_engine *engine;
235 	struct completion complete;
236 	int status;
237 	dma_addr_t dtx;
238 	struct descriptor *tx;
239 	dma_addr_t drx;
240 	struct descriptor *rx;
241 	int ctx;
242 	int crx;
243 	struct hwrng trng;
244 	unsigned long hwrng_stat_req;
245 	unsigned long hwrng_stat_bytes;
246 	unsigned long stat_irq;
247 	unsigned long stat_irq_tx;
248 	unsigned long stat_irq_rx;
249 	unsigned long stat_req;
250 	unsigned long fallback_sg_count_tx;
251 	unsigned long fallback_sg_count_rx;
252 	unsigned long fallback_not_same_len;
253 	unsigned long fallback_mod16;
254 	unsigned long fallback_align16;
255 #ifdef CONFIG_CRYPTO_DEV_SL3516_DEBUG
256 	struct dentry *dbgfs_dir;
257 	struct dentry *dbgfs_stats;
258 #endif
259 	void *pctrl;
260 	dma_addr_t dctrl;
261 };
262 
263 struct sginfo {
264 	u32 addr;
265 	u32 len;
266 };
267 
268 /*
269  * struct sl3516_ce_cipher_req_ctx - context for a skcipher request
270  * @t_src:		list of mapped SGs with their size
271  * @t_dst:		list of mapped SGs with their size
272  * @op_dir:		direction (encrypt vs decrypt) for this request
273  * @pctrllen:		the length of the ctrl packet
274  * @tqflag:		the TQflag to set in data packet
275  * @h			pointer to the pkt_control_cipher header
276  * @nr_sgs:		number of source SG
277  * @nr_sgd:		number of destination SG
278  * @fallback_req:	request struct for invoking the fallback skcipher TFM
279  */
280 struct sl3516_ce_cipher_req_ctx {
281 	struct sginfo t_src[MAXDESC];
282 	struct sginfo t_dst[MAXDESC];
283 	u32 op_dir;
284 	unsigned int pctrllen;
285 	u32 tqflag;
286 	struct pkt_control_cipher *h;
287 	int nr_sgs;
288 	int nr_sgd;
289 	struct skcipher_request fallback_req;   // keep at the end
290 };
291 
292 /*
293  * struct sl3516_ce_cipher_tfm_ctx - context for a skcipher TFM
294  * @key:		pointer to key data
295  * @keylen:		len of the key
296  * @ce:			pointer to the private data of driver handling this TFM
297  * @fallback_tfm:	pointer to the fallback TFM
298  */
299 struct sl3516_ce_cipher_tfm_ctx {
300 	u32 *key;
301 	u32 keylen;
302 	struct sl3516_ce_dev *ce;
303 	struct crypto_skcipher *fallback_tfm;
304 };
305 
306 /*
307  * struct sl3516_ce_alg_template - crypto_alg template
308  * @type:		the CRYPTO_ALG_TYPE for this template
309  * @mode:		value to be used in control packet for this algorithm
310  * @ce:			pointer to the sl3516_ce_dev structure associated with
311  *			this template
312  * @alg:		one of sub struct must be used
313  * @stat_req:		number of request done on this template
314  * @stat_fb:		number of request which has fallbacked
315  * @stat_bytes:		total data size done by this template
316  */
317 struct sl3516_ce_alg_template {
318 	u32 type;
319 	u32 mode;
320 	struct sl3516_ce_dev *ce;
321 	union {
322 		struct skcipher_engine_alg skcipher;
323 	} alg;
324 	unsigned long stat_req;
325 	unsigned long stat_fb;
326 	unsigned long stat_bytes;
327 };
328 
329 int sl3516_ce_enqueue(struct crypto_async_request *areq, u32 type);
330 
331 int sl3516_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
332 			 unsigned int keylen);
333 int sl3516_ce_cipher_init(struct crypto_tfm *tfm);
334 void sl3516_ce_cipher_exit(struct crypto_tfm *tfm);
335 int sl3516_ce_skdecrypt(struct skcipher_request *areq);
336 int sl3516_ce_skencrypt(struct skcipher_request *areq);
337 
338 int sl3516_ce_run_task(struct sl3516_ce_dev *ce,
339 		       struct sl3516_ce_cipher_req_ctx *rctx, const char *name);
340 
341 int sl3516_ce_rng_register(struct sl3516_ce_dev *ce);
342 void sl3516_ce_rng_unregister(struct sl3516_ce_dev *ce);
343 int sl3516_ce_handle_cipher_request(struct crypto_engine *engine, void *areq);
344