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 */
96struct 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 */
172struct 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
187struct 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 */
195struct 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 */
229struct 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
263struct 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 */
280struct 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 */
299struct 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 */
317struct 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
329int sl3516_ce_enqueue(struct crypto_async_request *areq, u32 type);
330
331int sl3516_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
332			 unsigned int keylen);
333int sl3516_ce_cipher_init(struct crypto_tfm *tfm);
334void sl3516_ce_cipher_exit(struct crypto_tfm *tfm);
335int sl3516_ce_skdecrypt(struct skcipher_request *areq);
336int sl3516_ce_skencrypt(struct skcipher_request *areq);
337
338int sl3516_ce_run_task(struct sl3516_ce_dev *ce,
339		       struct sl3516_ce_cipher_req_ctx *rctx, const char *name);
340
341int sl3516_ce_rng_register(struct sl3516_ce_dev *ce);
342void sl3516_ce_rng_unregister(struct sl3516_ce_dev *ce);
343int sl3516_ce_handle_cipher_request(struct crypto_engine *engine, void *areq);
344