1 // SPDX-License-Identifier: GPL-2.0
3  * OTP Memory controller
13 #include <linux/nvmem-provider.h>
28 #define MCHP_OTPC_NAME			"mchp-otpc"
32  * struct mchp_otpc - OTPC private data structure
35  * @packets: list of packets in OTP memory
36  * @npackets: number of packets in OTP memory
46  * struct mchp_otpc_packet - OTPC packet data structure
49  * @offset: packet offset (in words) in OTP memory
62 	if (id >= otpc->npackets)  in mchp_otpc_id_to_packet()
65 	list_for_each_entry(packet, &otpc->packets, list) {  in mchp_otpc_id_to_packet()
66 		if (packet->id == id)  in mchp_otpc_id_to_packet()
79 	tmp = readl_relaxed(otpc->base + MCHP_OTPC_MR);  in mchp_otpc_prepare_read()
82 	writel_relaxed(tmp, otpc->base + MCHP_OTPC_MR);  in mchp_otpc_prepare_read()
85 	tmp = readl_relaxed(otpc->base + MCHP_OTPC_CR);  in mchp_otpc_prepare_read()
87 	writel_relaxed(tmp, otpc->base + MCHP_OTPC_CR);  in mchp_otpc_prepare_read()
91 				 10000, 2000, false, otpc->base + MCHP_OTPC_SR);  in mchp_otpc_prepare_read()
100  * -------------  ----------------     ---------
102  * 0x0            +------------+   <-- packet 0
104  * 0x4            +------------+
109  * offset1        +------------+   <-- packet 1
111  * offset1 + 0x4  +------------+
116  * offset2        +------------+   <-- packet 2
120  * offsetN        +------------+   <-- packet N
122  * offsetN + 0x4  +------------+
127  *                +------------+
130  * payload N-1.
143  * packet. The user will have to be aware of the memory footprint before doing
164 		return -EINVAL;  in mchp_otpc_read()
165 	offset = packet->offset;  in mchp_otpc_read()
173 		*buf++ = readl_relaxed(otpc->base + MCHP_OTPC_HR);  in mchp_otpc_read()
180 		payload_size = FIELD_GET(MCHP_OTPC_HR_SIZE, *(buf - 1));  in mchp_otpc_read()
181 		writel_relaxed(0UL, otpc->base + MCHP_OTPC_AR);  in mchp_otpc_read()
183 			*buf++ = readl_relaxed(otpc->base + MCHP_OTPC_DR);  in mchp_otpc_read()
186 			payload_size--;  in mchp_otpc_read()
199 	INIT_LIST_HEAD(&otpc->packets);  in mchp_otpc_init_packets_list()
207 		word = readl_relaxed(otpc->base + MCHP_OTPC_HR);  in mchp_otpc_init_packets_list()
212 		packet = devm_kzalloc(otpc->dev, sizeof(*packet), GFP_KERNEL);  in mchp_otpc_init_packets_list()
214 			return -ENOMEM;  in mchp_otpc_init_packets_list()
216 		packet->id = id++;  in mchp_otpc_init_packets_list()
217 		packet->offset = word_pos;  in mchp_otpc_init_packets_list()
218 		INIT_LIST_HEAD(&packet->list);  in mchp_otpc_init_packets_list()
219 		list_add_tail(&packet->list, &otpc->packets);  in mchp_otpc_init_packets_list()
229 	otpc->npackets = npackets;  in mchp_otpc_init_packets_list()
250 	otpc = devm_kzalloc(&pdev->dev, sizeof(*otpc), GFP_KERNEL);  in mchp_otpc_probe()
252 		return -ENOMEM;  in mchp_otpc_probe()
254 	otpc->base = devm_platform_ioremap_resource(pdev, 0);  in mchp_otpc_probe()
255 	if (IS_ERR(otpc->base))  in mchp_otpc_probe()
256 		return PTR_ERR(otpc->base);  in mchp_otpc_probe()
258 	otpc->dev = &pdev->dev;  in mchp_otpc_probe()
263 	mchp_nvmem_config.dev = otpc->dev;  in mchp_otpc_probe()
267 	nvmem = devm_nvmem_register(&pdev->dev, &mchp_nvmem_config);  in mchp_otpc_probe()
273 	{ .compatible = "microchip,sama7g5-otpc", },