1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause */
15 #define JENT_TEST_RINGBUFFER_MASK	(JENT_TEST_RINGBUFFER_SIZE - 1)
31  * boot variable:
32  * 0 ==> No boot test, gathering of runtime data allowed
33  * 1 ==> Boot test enabled and ready for collecting data, gathering runtime
35  * 2 ==> Boot test completed and disabled, gathering of runtime data is
43 	spin_lock_irqsave(&data->lock, flags);  in jent_testing_reset()
44 	data->rb_reader = 0;  in jent_testing_reset()
45 	atomic_set(&data->rb_writer, 0);  in jent_testing_reset()
46 	spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_reset()
49 static void jent_testing_data_init(struct jent_testing *data, u32 boot)  in jent_testing_data_init()  argument
52 	 * The boot time testing implies we have a running test. If the  in jent_testing_data_init()
56 	if (boot)  in jent_testing_data_init()
60 	atomic_set(&data->jent_testing_enabled, 1);  in jent_testing_data_init()
64 static void jent_testing_fini(struct jent_testing *data, u32 boot)  in jent_testing_fini()  argument
66 	/* If we have boot data, we do not reset yet to allow data to be read */  in jent_testing_fini()
67 	if (boot)  in jent_testing_fini()
70 	atomic_set(&data->jent_testing_enabled, 0);  in jent_testing_fini()
76 			       u32 *boot)  in jent_testing_store()  argument
80 	if (!atomic_read(&data->jent_testing_enabled) && (*boot != 1))  in jent_testing_store()
83 	spin_lock_irqsave(&data->lock, flags);  in jent_testing_store()
86 	 * Disable entropy testing for boot time testing after ring buffer  in jent_testing_store()
89 	if (*boot) {  in jent_testing_store()
90 		if (((u32)atomic_read(&data->rb_writer)) >  in jent_testing_store()
92 			*boot = 2;  in jent_testing_store()
94 			spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_store()
98 		if (atomic_read(&data->rb_writer) == 1)  in jent_testing_store()
102 	data->jent_testing_rb[((u32)atomic_read(&data->rb_writer)) &  in jent_testing_store()
104 	atomic_inc(&data->rb_writer);  in jent_testing_store()
106 	spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_store()
108 	if (wq_has_sleeper(&data->read_wait))  in jent_testing_store()
109 		wake_up_interruptible(&data->read_wait);  in jent_testing_store()
116 	return ((((u32)atomic_read(&data->rb_writer)) &  in jent_testing_have_data()
118 		 (data->rb_reader & JENT_TEST_RINGBUFFER_MASK));  in jent_testing_have_data()
121 static int jent_testing_reader(struct jent_testing *data, u32 *boot,  in jent_testing_reader()  argument
127 	jent_testing_data_init(data, *boot);  in jent_testing_reader()
130 		u32 writer = (u32)atomic_read(&data->rb_writer);  in jent_testing_reader()
132 		spin_lock_irqsave(&data->lock, flags);  in jent_testing_reader()
135 		if (!writer || (writer == data->rb_reader)) {  in jent_testing_reader()
137 			spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_reader()
140 			 * Now we gathered all boot data, enable regular data  in jent_testing_reader()
143 			if (*boot) {  in jent_testing_reader()
144 				*boot = 0;  in jent_testing_reader()
148 			wait_event_interruptible(data->read_wait,  in jent_testing_reader()
151 				collected_data = -ERESTARTSYS;  in jent_testing_reader()
158 		/* We copy out word-wise */  in jent_testing_reader()
160 			spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_reader()
164 		memcpy(outbuf, &data->jent_testing_rb[data->rb_reader],  in jent_testing_reader()
166 		data->rb_reader++;  in jent_testing_reader()
168 		spin_unlock_irqrestore(&data->lock, flags);  in jent_testing_reader()
171 		outbuflen -= sizeof(u64);  in jent_testing_reader()
176 	jent_testing_fini(data, *boot);  in jent_testing_reader()
192 	 * 1000 samples due to the SP800-90B requirements. However, due to  in jent_testing_extract_user()
200 		return -ENOMEM;  in jent_testing_extract_user()
210 					ret = -ERESTARTSYS;  in jent_testing_extract_user()
224 			ret = -EFAULT;  in jent_testing_extract_user()
228 		nbytes -= i;  in jent_testing_extract_user()
241 /************** Raw High-Resolution Timer Entropy Data Handling **************/
246 …"Enable gathering boot time high resolution timer entropy of the first Jitter RNG entropy events");