xref: /rk3399_ARM-atf/plat/arm/board/arm_fpga/fpga_bl31_setup.c (revision 283e5595afa28a5930ac5f0dcdf7c18804221070)
1 /*
2  * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 
10 #include <common/fdt_fixup.h>
11 #include <common/fdt_wrappers.h>
12 #include <drivers/arm/gicv3.h>
13 #include <drivers/delay_timer.h>
14 #include <drivers/generic_delay_timer.h>
15 #include <libfdt.h>
16 
17 #include "fpga_private.h"
18 #include <plat/common/platform.h>
19 #include <platform_def.h>
20 
21 static entry_point_info_t bl33_image_ep_info;
22 volatile uint32_t secondary_core_spinlock;
23 
24 uintptr_t plat_get_ns_image_entrypoint(void)
25 {
26 #ifdef PRELOADED_BL33_BASE
27 	return PRELOADED_BL33_BASE;
28 #else
29 	return 0ULL;
30 #endif
31 }
32 
33 uint32_t fpga_get_spsr_for_bl33_entry(void)
34 {
35 	return SPSR_64(MODE_EL2, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
36 }
37 
38 void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
39 				u_register_t arg2, u_register_t arg3)
40 {
41 	/* Add this core to the VALID mpids list */
42 	fpga_valid_mpids[plat_my_core_pos()] = VALID_MPID;
43 
44 	/*
45 	 * Notify the secondary CPUs that the C runtime is ready
46 	 * so they can announce themselves.
47 	 */
48 	secondary_core_spinlock = C_RUNTIME_READY_KEY;
49 	dsbish();
50 	sev();
51 
52 	fpga_console_init();
53 
54 	bl33_image_ep_info.pc = plat_get_ns_image_entrypoint();
55 	bl33_image_ep_info.spsr = fpga_get_spsr_for_bl33_entry();
56 	SET_SECURITY_STATE(bl33_image_ep_info.h.attr, NON_SECURE);
57 
58 	/* Set x0-x3 for the primary CPU as expected by the kernel */
59 	bl33_image_ep_info.args.arg0 = (u_register_t)FPGA_PRELOADED_DTB_BASE;
60 	bl33_image_ep_info.args.arg1 = 0U;
61 	bl33_image_ep_info.args.arg2 = 0U;
62 	bl33_image_ep_info.args.arg3 = 0U;
63 }
64 
65 void bl31_plat_arch_setup(void)
66 {
67 }
68 
69 void bl31_platform_setup(void)
70 {
71 	/* Write frequency to CNTCRL and initialize timer */
72 	generic_delay_timer_init();
73 
74 	/*
75 	 * Before doing anything else, wait for some time to ensure that
76 	 * the secondary CPUs have populated the fpga_valid_mpids array.
77 	 * As the number of secondary cores is unknown and can even be 0,
78 	 * it is not possible to rely on any signal from them, so use a
79 	 * delay instead.
80 	 */
81 	mdelay(5);
82 
83 	/*
84 	 * On the event of a cold reset issued by, for instance, a reset pin
85 	 * assertion, we cannot guarantee memory to be initialized to zero.
86 	 * In such scenario, if the secondary cores reached
87 	 * plat_secondary_cold_boot_setup before the primary one initialized
88 	 * .BSS, we could end up having a race condition if the spinlock
89 	 * was not cleared before.
90 	 *
91 	 * Similarly, if there were a reset before the spinlock had been
92 	 * cleared, the secondary cores would find the lock opened before
93 	 * .BSS is cleared, causing another race condition.
94 	 *
95 	 * So clean the spinlock as soon as we think it is safe to reduce the
96 	 * chances of any race condition on a reset.
97 	 */
98 	secondary_core_spinlock = 0UL;
99 
100 	/* Initialize the GIC driver, cpu and distributor interfaces */
101 	plat_fpga_gic_init();
102 }
103 
104 entry_point_info_t *bl31_plat_get_next_image_ep_info(uint32_t type)
105 {
106 	entry_point_info_t *next_image_info;
107 	next_image_info = &bl33_image_ep_info;
108 
109 	/* Only expecting BL33: the kernel will run in EL2NS */
110 	assert(type == NON_SECURE);
111 
112 	/* None of the images can have 0x0 as the entrypoint */
113 	if (next_image_info->pc) {
114 		return next_image_info;
115 	} else {
116 		return NULL;
117 	}
118 }
119 
120 unsigned int plat_get_syscnt_freq2(void)
121 {
122 	const void *fdt = (void *)(uintptr_t)FPGA_PRELOADED_DTB_BASE;
123 	int node;
124 
125 	node = fdt_node_offset_by_compatible(fdt, 0, "arm,armv8-timer");
126 	if (node < 0) {
127 		return FPGA_DEFAULT_TIMER_FREQUENCY;
128 	}
129 
130 	return fdt_read_uint32_default(fdt, node, "clock-frequency",
131 				       FPGA_DEFAULT_TIMER_FREQUENCY);
132 }
133 
134 static void fpga_prepare_dtb(void)
135 {
136 	void *fdt = (void *)(uintptr_t)FPGA_PRELOADED_DTB_BASE;
137 	const char *cmdline = (void *)(uintptr_t)FPGA_PRELOADED_CMD_LINE;
138 	int err;
139 
140 	err = fdt_open_into(fdt, fdt, FPGA_MAX_DTB_SIZE);
141 	if (err < 0) {
142 		ERROR("cannot open devicetree at %p: %d\n", fdt, err);
143 		panic();
144 	}
145 
146 	/* Check for the command line signature. */
147 	if (!strncmp(cmdline, "CMD:", 4)) {
148 		int chosen;
149 
150 		INFO("using command line at 0x%x\n", FPGA_PRELOADED_CMD_LINE);
151 
152 		chosen = fdt_add_subnode(fdt, 0, "chosen");
153 		if (chosen == -FDT_ERR_EXISTS) {
154 			chosen = fdt_path_offset(fdt, "/chosen");
155 		}
156 		if (chosen < 0) {
157 			ERROR("cannot find /chosen node: %d\n", chosen);
158 		} else {
159 			const char *eol;
160 			char nul = 0;
161 			int slen;
162 
163 			/*
164 			 * There is most likely an EOL at the end of the
165 			 * command line, make sure we terminate the line there.
166 			 * We can't replace the EOL with a NUL byte in the
167 			 * source, as this is in read-only memory. So we first
168 			 * create the property without any termination, then
169 			 * append a single NUL byte.
170 			 */
171 			eol = strchr(cmdline, '\n');
172 			if (!eol) {
173 				eol = strchr(cmdline, 0);
174 			}
175 			/* Skip the signature and omit the EOL/NUL byte. */
176 			slen = eol - (cmdline + 4);
177 
178 			/*
179 			 * Let's limit the size of the property, just in case
180 			 * we find the signature by accident. The Linux kernel
181 			 * limits to 4096 characters at most (in fact 2048 for
182 			 * arm64), so that sounds like a reasonable number.
183 			 */
184 			if (slen > 4095) {
185 				slen = 4095;
186 			}
187 			err = fdt_setprop(fdt, chosen, "bootargs",
188 					  cmdline + 4, slen);
189 			if (!err) {
190 				err = fdt_appendprop(fdt, chosen, "bootargs",
191 						     &nul, 1);
192 			}
193 			if (err) {
194 				ERROR("Could not set command line: %d\n", err);
195 			}
196 		}
197 	}
198 
199 	if (err < 0) {
200 		ERROR("Error %d extending Device Tree\n", err);
201 		panic();
202 	}
203 
204 	err = fdt_add_cpus_node(fdt, FPGA_MAX_PE_PER_CPU,
205 				FPGA_MAX_CPUS_PER_CLUSTER,
206 				FPGA_MAX_CLUSTER_COUNT);
207 
208 	if (err == -EEXIST) {
209 		WARN("Not overwriting already existing /cpus node in DTB\n");
210 	} else {
211 		if (err < 0) {
212 			ERROR("Error %d creating the /cpus DT node\n", err);
213 			panic();
214 		} else {
215 			unsigned int nr_cores = fpga_get_nr_gic_cores();
216 
217 			INFO("Adjusting GICR DT region to cover %u cores\n",
218 			      nr_cores);
219 			err = fdt_adjust_gic_redist(fdt, nr_cores,
220 						    1U << GICR_PCPUBASE_SHIFT);
221 			if (err < 0) {
222 				ERROR("Error %d fixing up GIC DT node\n", err);
223 			}
224 		}
225 	}
226 
227 	err = fdt_pack(fdt);
228 	if (err < 0) {
229 		ERROR("Failed to pack Device Tree at %p: error %d\n", fdt, err);
230 	}
231 
232 	clean_dcache_range((uintptr_t)fdt, fdt_blob_size(fdt));
233 }
234 
235 void bl31_plat_runtime_setup(void)
236 {
237 	fpga_prepare_dtb();
238 }
239 
240 void bl31_plat_enable_mmu(uint32_t flags)
241 {
242 	/* TODO: determine if MMU needs to be enabled */
243 }
244