1 /*
2  * Copyright (c) 2017-2022, Arm Limited and Contributors. All rights reserved.
3  * Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
4  *
5  * SPDX-License-Identifier: BSD-3-Clause
6  */
7 
8 /*
9  * Driver for GIC-500 and GIC-600 specific features. This driver only
10  * overrides APIs that are different to those generic ones in GICv3
11  * driver.
12  *
13  * GIC-600 supports independently power-gating redistributor interface.
14  */
15 
16 #include <assert.h>
17 
18 #include <arch_helpers.h>
19 #include <common/debug.h>
20 #include <drivers/arm/arm_gicv3_common.h>
21 #include <drivers/arm/gicv3.h>
22 
23 #include "gicv3_private.h"
24 
25 /* GIC-600 specific register offsets */
26 #define GICR_PWRR			0x24U
27 
28 /* GICR_PWRR fields */
29 #define PWRR_RDPD_SHIFT			0
30 #define PWRR_RDAG_SHIFT			1
31 #define PWRR_RDGPD_SHIFT		2
32 #define PWRR_RDGPO_SHIFT		3
33 
34 #define PWRR_RDPD			(1U << PWRR_RDPD_SHIFT)
35 #define PWRR_RDAG			(1U << PWRR_RDAG_SHIFT)
36 #define PWRR_RDGPD			(1U << PWRR_RDGPD_SHIFT)
37 #define PWRR_RDGPO			(1U << PWRR_RDGPO_SHIFT)
38 
39 /*
40  * Values to write to GICR_PWRR register to power redistributor
41  * for operating through the core (GICR_PWRR.RDAG = 0)
42  */
43 #define PWRR_ON				(0U << PWRR_RDPD_SHIFT)
44 #define PWRR_OFF			(1U << PWRR_RDPD_SHIFT)
45 
46 static bool gic600_errata_wa_2384374 __unused;
47 
48 #if GICV3_SUPPORT_GIC600
49 
50 /* GIC-600/700 specific accessor functions */
gicr_write_pwrr(uintptr_t base,unsigned int val)51 static void gicr_write_pwrr(uintptr_t base, unsigned int val)
52 {
53 	mmio_write_32(base + GICR_PWRR, val);
54 }
55 
gicr_read_pwrr(uintptr_t base)56 static uint32_t gicr_read_pwrr(uintptr_t base)
57 {
58 	return mmio_read_32(base + GICR_PWRR);
59 }
60 
gicr_wait_group_not_in_transit(uintptr_t base)61 static void gicr_wait_group_not_in_transit(uintptr_t base)
62 {
63 	uint32_t pwrr;
64 
65 	do {
66 		pwrr = gicr_read_pwrr(base);
67 
68 	/* Check group not transitioning: RDGPD == RDGPO */
69 	} while (((pwrr & PWRR_RDGPD) >> PWRR_RDGPD_SHIFT) !=
70 		 ((pwrr & PWRR_RDGPO) >> PWRR_RDGPO_SHIFT));
71 }
72 
gic600_pwr_on(uintptr_t base)73 static void gic600_pwr_on(uintptr_t base)
74 {
75 	do {	/* Wait until group not transitioning */
76 		gicr_wait_group_not_in_transit(base);
77 
78 		/* Power on redistributor */
79 		gicr_write_pwrr(base, PWRR_ON);
80 
81 		/*
82 		 * Wait until the power on state is reflected.
83 		 * If RDPD == 0 then powered on.
84 		 */
85 	} while ((gicr_read_pwrr(base) & PWRR_RDPD) != PWRR_ON);
86 }
87 
gic600_pwr_off(uintptr_t base)88 static void gic600_pwr_off(uintptr_t base)
89 {
90 	/* Wait until group not transitioning */
91 	gicr_wait_group_not_in_transit(base);
92 
93 	/* Power off redistributor */
94 	gicr_write_pwrr(base, PWRR_OFF);
95 
96 	/*
97 	 * If this is the last man, turning this redistributor frame off will
98 	 * result in the group itself being powered off and RDGPD = 1.
99 	 * In that case, wait as long as it's in transition, or has aborted
100 	 * the transition altogether for any reason.
101 	 */
102 	if ((gicr_read_pwrr(base) & PWRR_RDGPD) != 0U) {
103 		/* Wait until group not transitioning */
104 		gicr_wait_group_not_in_transit(base);
105 	}
106 }
107 
get_gicr_base(unsigned int proc_num)108 static uintptr_t get_gicr_base(unsigned int proc_num)
109 {
110 	uintptr_t gicr_base;
111 
112 	assert(gicv3_driver_data != NULL);
113 	assert(proc_num < gicv3_driver_data->rdistif_num);
114 	assert(gicv3_driver_data->rdistif_base_addrs != NULL);
115 
116 	gicr_base = gicv3_driver_data->rdistif_base_addrs[proc_num];
117 	assert(gicr_base != 0UL);
118 
119 	return gicr_base;
120 }
121 
gicv3_redists_need_power_mgmt(uintptr_t gicr_base)122 static bool gicv3_redists_need_power_mgmt(uintptr_t gicr_base)
123 {
124 	uint32_t reg = mmio_read_32(gicr_base + GICR_IIDR);
125 
126 	/*
127 	 * The Arm GIC-600 and GIC-700 models have their redistributors
128 	 * powered down at reset.
129 	 */
130 	return (((reg & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_600) ||
131 		((reg & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_600AE) ||
132 		((reg & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_700));
133 }
134 
135 #endif	/* GICV3_SUPPORT_GIC600 */
136 
gicv3_distif_pre_save(unsigned int proc_num)137 void gicv3_distif_pre_save(unsigned int proc_num)
138 {
139 	arm_gicv3_distif_pre_save(proc_num);
140 }
141 
gicv3_distif_post_restore(unsigned int proc_num)142 void gicv3_distif_post_restore(unsigned int proc_num)
143 {
144 	arm_gicv3_distif_post_restore(proc_num);
145 }
146 
147 /*
148  * Power off GIC-600 redistributor (if configured and detected)
149  */
gicv3_rdistif_off(unsigned int proc_num)150 void gicv3_rdistif_off(unsigned int proc_num)
151 {
152 #if GICV3_SUPPORT_GIC600
153 	uintptr_t gicr_base = get_gicr_base(proc_num);
154 
155 	/* Attempt to power redistributor off */
156 	if (gicv3_redists_need_power_mgmt(gicr_base)) {
157 		gic600_pwr_off(gicr_base);
158 	}
159 #endif
160 }
161 
162 /*
163  * Power on GIC-600 redistributor (if configured and detected)
164  */
gicv3_rdistif_on(unsigned int proc_num)165 void gicv3_rdistif_on(unsigned int proc_num)
166 {
167 #if GICV3_SUPPORT_GIC600
168 	uintptr_t gicr_base = get_gicr_base(proc_num);
169 
170 	/* Power redistributor on */
171 	if (gicv3_redists_need_power_mgmt(gicr_base)) {
172 		gic600_pwr_on(gicr_base);
173 	}
174 #endif
175 }
176 
177 #if GIC600_ERRATA_WA_2384374
178 /*******************************************************************************
179  * Apply part 2 of workaround for errata-2384374 as per SDEN:
180  * https://developer.arm.com/documentation/sden892601/latest/
181  ******************************************************************************/
gicv3_apply_errata_wa_2384374(uintptr_t gicr_base)182 void gicv3_apply_errata_wa_2384374(uintptr_t gicr_base)
183 {
184 	if (gic600_errata_wa_2384374) {
185 		uint32_t gicr_ctlr_val = gicr_read_ctlr(gicr_base);
186 
187 		gicr_write_ctlr(gicr_base, gicr_ctlr_val |
188 				(GICR_CTLR_DPG0_BIT | GICR_CTLR_DPG1NS_BIT |
189 				GICR_CTLR_DPG1S_BIT));
190 		gicr_write_ctlr(gicr_base, gicr_ctlr_val &
191 				~(GICR_CTLR_DPG0_BIT | GICR_CTLR_DPG1NS_BIT |
192 				  GICR_CTLR_DPG1S_BIT));
193 	}
194 }
195 #endif /* GIC600_ERRATA_WA_2384374 */
196 
gicv3_check_erratas_applies(uintptr_t gicd_base)197 void gicv3_check_erratas_applies(uintptr_t gicd_base)
198 {
199 	unsigned int gic_prod_id;
200 	uint8_t gic_rev;
201 
202 	assert(gicd_base != 0UL);
203 
204 	gicv3_get_component_prodid_rev(gicd_base, &gic_prod_id, &gic_rev);
205 
206 	/*
207 	 * This workaround applicable only to GIC600 and GIC600AE products with
208 	 * revision less than r1p6 and r0p2 respectively.
209 	 * As per GIC600/GIC600AE specification -
210 	 * r1p6 = 0x17 => GICD_IIDR[19:12]
211 	 * r0p2 = 0x04 => GICD_IIDR[19:12]
212 	 */
213 	if ((gic_prod_id == GIC_PRODUCT_ID_GIC600) ||
214 		    (gic_prod_id == GIC_PRODUCT_ID_GIC600AE)) {
215 		if (((gic_prod_id == GIC_PRODUCT_ID_GIC600) &&
216 		     (gic_rev <= GIC_REV(GIC_VARIANT_R1, GIC_REV_P6))) ||
217 		     ((gic_prod_id == GIC_PRODUCT_ID_GIC600AE) &&
218 		     (gic_rev <= GIC_REV(GIC_VARIANT_R0, GIC_REV_P2)))) {
219 #if GIC600_ERRATA_WA_2384374
220 			gic600_errata_wa_2384374 = true;
221 			VERBOSE("%s applies\n",
222 				"GIC600/GIC600AE errata workaround 2384374");
223 #else
224 			WARN("%s missing\n",
225 			     "GIC600/GIC600AE errata workaround 2384374");
226 #endif /* GIC600_ERRATA_WA_2384374 */
227 		} else {
228 			VERBOSE("%s not applies\n",
229 				"GIC600/GIC600AE errata workaround 2384374");
230 		}
231 	}
232 }
233