1 /*
2  * Copyright 2019-2022 NXP
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <bl31/interrupt_mgmt.h>
8 #include <common/runtime_svc.h>
9 #include <lib/mmio.h>
10 #include <lib/spinlock.h>
11 #include <plat/common/platform.h>
12 
13 #include <dram.h>
14 
15 #define IMX_SIP_DDR_DVFS_GET_FREQ_COUNT		0x10
16 #define IMX_SIP_DDR_DVFS_GET_FREQ_INFO		0x11
17 
18 struct dram_info dram_info;
19 
20 /* lock used for DDR DVFS */
21 spinlock_t dfs_lock;
22 
23 static volatile uint32_t wfe_done;
24 static volatile bool wait_ddrc_hwffc_done = true;
25 static unsigned int dev_fsp = 0x1;
26 
27 static uint32_t fsp_init_reg[3][4] = {
28 	{ DDRC_INIT3(0), DDRC_INIT4(0), DDRC_INIT6(0), DDRC_INIT7(0) },
29 	{ DDRC_FREQ1_INIT3(0), DDRC_FREQ1_INIT4(0), DDRC_FREQ1_INIT6(0), DDRC_FREQ1_INIT7(0) },
30 	{ DDRC_FREQ2_INIT3(0), DDRC_FREQ2_INIT4(0), DDRC_FREQ2_INIT6(0), DDRC_FREQ2_INIT7(0) },
31 };
32 
get_mr_values(uint32_t (* mr_value)[8])33 static void get_mr_values(uint32_t (*mr_value)[8])
34 {
35 	uint32_t init_val;
36 	unsigned int i, fsp_index;
37 
38 	for (fsp_index = 0U; fsp_index < 3U; fsp_index++) {
39 		for (i = 0U; i < 4U; i++) {
40 			init_val = mmio_read_32(fsp_init_reg[fsp_index][i]);
41 			mr_value[fsp_index][2*i] = init_val >> 16;
42 			mr_value[fsp_index][2*i + 1] = init_val & 0xFFFF;
43 		}
44 	}
45 }
46 
47 /* Restore the ddrc configs */
dram_umctl2_init(struct dram_timing_info * timing)48 void dram_umctl2_init(struct dram_timing_info *timing)
49 {
50 	struct dram_cfg_param *ddrc_cfg = timing->ddrc_cfg;
51 	unsigned int i;
52 
53 	for (i = 0U; i < timing->ddrc_cfg_num; i++) {
54 		mmio_write_32(ddrc_cfg->reg, ddrc_cfg->val);
55 		ddrc_cfg++;
56 	}
57 
58 	/* set the default fsp to P0 */
59 	mmio_write_32(DDRC_MSTR2(0), 0x0);
60 }
61 
62 /* Restore the dram PHY config */
dram_phy_init(struct dram_timing_info * timing)63 void dram_phy_init(struct dram_timing_info *timing)
64 {
65 	struct dram_cfg_param *cfg = timing->ddrphy_cfg;
66 	unsigned int i;
67 
68 	/* Restore the PHY init config */
69 	cfg = timing->ddrphy_cfg;
70 	for (i = 0U; i < timing->ddrphy_cfg_num; i++) {
71 		dwc_ddrphy_apb_wr(cfg->reg, cfg->val);
72 		cfg++;
73 	}
74 
75 	/* Restore the DDR PHY CSRs */
76 	cfg = timing->ddrphy_trained_csr;
77 	for (i = 0U; i < timing->ddrphy_trained_csr_num; i++) {
78 		dwc_ddrphy_apb_wr(cfg->reg, cfg->val);
79 		cfg++;
80 	}
81 
82 	/* Load the PIE image */
83 	cfg = timing->ddrphy_pie;
84 	for (i = 0U; i < timing->ddrphy_pie_num; i++) {
85 		dwc_ddrphy_apb_wr(cfg->reg, cfg->val);
86 		cfg++;
87 	}
88 }
89 
90 /* EL3 SGI-8 IPI handler for DDR Dynamic frequency scaling */
waiting_dvfs(uint32_t id,uint32_t flags,void * handle,void * cookie)91 static uint64_t waiting_dvfs(uint32_t id, uint32_t flags,
92 				void *handle, void *cookie)
93 {
94 	uint64_t mpidr = read_mpidr_el1();
95 	unsigned int cpu_id = MPIDR_AFFLVL0_VAL(mpidr);
96 	uint32_t irq;
97 
98 	irq = plat_ic_acknowledge_interrupt();
99 	if (irq < 1022U) {
100 		plat_ic_end_of_interrupt(irq);
101 	}
102 
103 	/* set the WFE done status */
104 	spin_lock(&dfs_lock);
105 	wfe_done |= (1 << cpu_id * 8);
106 	dsb();
107 	spin_unlock(&dfs_lock);
108 
109 	while (1) {
110 		/* ddr frequency change done */
111 		if (!wait_ddrc_hwffc_done)
112 			break;
113 
114 		wfe();
115 	}
116 
117 	return 0;
118 }
119 
dram_info_init(unsigned long dram_timing_base)120 void dram_info_init(unsigned long dram_timing_base)
121 {
122 	uint32_t ddrc_mstr, current_fsp;
123 	unsigned int idx = 0;
124 	uint32_t flags = 0;
125 	uint32_t rc;
126 	unsigned int i;
127 
128 	/* Get the dram type & rank */
129 	ddrc_mstr = mmio_read_32(DDRC_MSTR(0));
130 
131 	dram_info.dram_type = ddrc_mstr & DDR_TYPE_MASK;
132 	dram_info.num_rank = (ddrc_mstr >> 24) & ACTIVE_RANK_MASK;
133 
134 	/* Get current fsp info */
135 	current_fsp = mmio_read_32(DDRC_DFIMISC(0)) & 0xf;
136 	dram_info.boot_fsp = current_fsp;
137 	dram_info.current_fsp = current_fsp;
138 
139 	get_mr_values(dram_info.mr_table);
140 
141 	dram_info.timing_info = (struct dram_timing_info *)dram_timing_base;
142 
143 	/* get the num of supported fsp */
144 	for (i = 0U; i < 4U; ++i) {
145 		if (!dram_info.timing_info->fsp_table[i]) {
146 			break;
147 		}
148 		idx = i;
149 	}
150 	dram_info.num_fsp = i;
151 
152 	/* check if has bypass mode support */
153 	if (dram_info.timing_info->fsp_table[idx] < 666) {
154 		dram_info.bypass_mode = true;
155 	} else {
156 		dram_info.bypass_mode = false;
157 	}
158 
159 	/* Register the EL3 handler for DDR DVFS */
160 	set_interrupt_rm_flag(flags, NON_SECURE);
161 	rc = register_interrupt_type_handler(INTR_TYPE_EL3, waiting_dvfs, flags);
162 	if (rc != 0) {
163 		panic();
164 	}
165 }
166 
167 
168 /*
169  * For each freq return the following info:
170  *
171  * r1: data rate
172  * r2: 1 + dram_core parent
173  * r3: 1 + dram_alt parent index
174  * r4: 1 + dram_apb parent index
175  *
176  * The parent indices can be used by an OS who manages source clocks to enabled
177  * them ahead of the switch.
178  *
179  * A parent value of "0" means "don't care".
180  *
181  * Current implementation of freq switch is hardcoded in
182  * plat/imx/common/imx8m/clock.c but in theory this can be enhanced to support
183  * a wide variety of rates.
184  */
dram_dvfs_get_freq_info(void * handle,u_register_t index)185 int dram_dvfs_get_freq_info(void *handle, u_register_t index)
186 {
187 	switch (index) {
188 	case 0:
189 		 SMC_RET4(handle, dram_info.timing_info->fsp_table[0],
190 			1, 0, 5);
191 	case 1:
192 		if (!dram_info.bypass_mode) {
193 			SMC_RET4(handle, dram_info.timing_info->fsp_table[1],
194 				1, 0, 0);
195 		}
196 		SMC_RET4(handle, dram_info.timing_info->fsp_table[1],
197 			2, 2, 4);
198 	case 2:
199 		if (!dram_info.bypass_mode) {
200 			SMC_RET4(handle, dram_info.timing_info->fsp_table[2],
201 				1, 0, 0);
202 		}
203 		SMC_RET4(handle, dram_info.timing_info->fsp_table[2],
204 			2, 3, 3);
205 	case 3:
206 		 SMC_RET4(handle, dram_info.timing_info->fsp_table[3],
207 			1, 0, 0);
208 	default:
209 		SMC_RET1(handle, -3);
210 	}
211 }
212 
dram_dvfs_handler(uint32_t smc_fid,void * handle,u_register_t x1,u_register_t x2,u_register_t x3)213 int dram_dvfs_handler(uint32_t smc_fid, void *handle,
214 	u_register_t x1, u_register_t x2, u_register_t x3)
215 {
216 	uint64_t mpidr = read_mpidr_el1();
217 	unsigned int cpu_id = MPIDR_AFFLVL0_VAL(mpidr);
218 	unsigned int fsp_index = x1;
219 	uint32_t online_cores = x2;
220 
221 	if (x1 == IMX_SIP_DDR_DVFS_GET_FREQ_COUNT) {
222 		SMC_RET1(handle, dram_info.num_fsp);
223 	} else if (x1 == IMX_SIP_DDR_DVFS_GET_FREQ_INFO) {
224 		return dram_dvfs_get_freq_info(handle, x2);
225 	} else if (x1 < 4) {
226 		wait_ddrc_hwffc_done = true;
227 		dsb();
228 
229 		/* trigger the SGI IPI to info other cores */
230 		for (int i = 0; i < PLATFORM_CORE_COUNT; i++) {
231 			if (cpu_id != i && (online_cores & (0x1 << (i * 8)))) {
232 				plat_ic_raise_el3_sgi(0x8, i);
233 			}
234 		}
235 
236 		/* make sure all the core in WFE */
237 		online_cores &= ~(0x1 << (cpu_id * 8));
238 		while (1) {
239 			if (online_cores == wfe_done) {
240 				break;
241 			}
242 		}
243 
244 		/* flush the L1/L2 cache */
245 		dcsw_op_all(DCCSW);
246 
247 		if (dram_info.dram_type == DDRC_LPDDR4) {
248 			lpddr4_swffc(&dram_info, dev_fsp, fsp_index);
249 			dev_fsp = (~dev_fsp) & 0x1;
250 		} else if (dram_info.dram_type == DDRC_DDR4) {
251 			ddr4_swffc(&dram_info, fsp_index);
252 		}
253 
254 		dram_info.current_fsp = fsp_index;
255 		wait_ddrc_hwffc_done = false;
256 		wfe_done = 0;
257 		dsb();
258 		sev();
259 		isb();
260 	}
261 
262 	SMC_RET1(handle, 0);
263 }
264