xref: /openbmc/linux/arch/arm/mach-socfpga/ocram.c (revision 2364d423)
1 /*
2  * Copyright Altera Corporation (C) 2016. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 #include <linux/delay.h>
17 #include <linux/io.h>
18 #include <linux/genalloc.h>
19 #include <linux/module.h>
20 #include <linux/of_address.h>
21 #include <linux/of_platform.h>
22 
23 #include "core.h"
24 
25 #define ALTR_OCRAM_CLEAR_ECC          0x00000018
26 #define ALTR_OCRAM_ECC_EN             0x00000019
27 
28 void socfpga_init_ocram_ecc(void)
29 {
30 	struct device_node *np;
31 	void __iomem *mapped_ocr_edac_addr;
32 
33 	/* Find the OCRAM EDAC device tree node */
34 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-ocram-ecc");
35 	if (!np) {
36 		pr_err("Unable to find socfpga-ocram-ecc\n");
37 		return;
38 	}
39 
40 	mapped_ocr_edac_addr = of_iomap(np, 0);
41 	of_node_put(np);
42 	if (!mapped_ocr_edac_addr) {
43 		pr_err("Unable to map OCRAM ecc regs.\n");
44 		return;
45 	}
46 
47 	/* Clear any pending OCRAM ECC interrupts, then enable ECC */
48 	writel(ALTR_OCRAM_CLEAR_ECC, mapped_ocr_edac_addr);
49 	writel(ALTR_OCRAM_ECC_EN, mapped_ocr_edac_addr);
50 
51 	iounmap(mapped_ocr_edac_addr);
52 }
53 
54 /* Arria10 OCRAM Section */
55 #define ALTR_A10_ECC_CTRL_OFST          0x08
56 #define ALTR_A10_OCRAM_ECC_EN_CTL       (BIT(1) | BIT(0))
57 #define ALTR_A10_ECC_INITA              BIT(16)
58 
59 #define ALTR_A10_ECC_INITSTAT_OFST      0x0C
60 #define ALTR_A10_ECC_INITCOMPLETEA      BIT(0)
61 #define ALTR_A10_ECC_INITCOMPLETEB      BIT(8)
62 
63 #define ALTR_A10_ECC_ERRINTEN_OFST      0x10
64 #define ALTR_A10_ECC_SERRINTEN          BIT(0)
65 
66 #define ALTR_A10_ECC_INTSTAT_OFST       0x20
67 #define ALTR_A10_ECC_SERRPENA           BIT(0)
68 #define ALTR_A10_ECC_DERRPENA           BIT(8)
69 #define ALTR_A10_ECC_ERRPENA_MASK       (ALTR_A10_ECC_SERRPENA | \
70 					 ALTR_A10_ECC_DERRPENA)
71 /* ECC Manager Defines */
72 #define A10_SYSMGR_ECC_INTMASK_SET_OFST   0x94
73 #define A10_SYSMGR_ECC_INTMASK_CLR_OFST   0x98
74 #define A10_SYSMGR_ECC_INTMASK_OCRAM      BIT(1)
75 
76 #define ALTR_A10_ECC_INIT_WATCHDOG_10US   10000
77 
78 static inline void ecc_set_bits(u32 bit_mask, void __iomem *ioaddr)
79 {
80 	u32 value = readl(ioaddr);
81 
82 	value |= bit_mask;
83 	writel(value, ioaddr);
84 }
85 
86 static inline void ecc_clear_bits(u32 bit_mask, void __iomem *ioaddr)
87 {
88 	u32 value = readl(ioaddr);
89 
90 	value &= ~bit_mask;
91 	writel(value, ioaddr);
92 }
93 
94 static inline int ecc_test_bits(u32 bit_mask, void __iomem *ioaddr)
95 {
96 	u32 value = readl(ioaddr);
97 
98 	return (value & bit_mask) ? 1 : 0;
99 }
100 
101 /*
102  * This function uses the memory initialization block in the Arria10 ECC
103  * controller to initialize/clear the entire memory data and ECC data.
104  */
105 static int altr_init_memory_port(void __iomem *ioaddr)
106 {
107 	int limit = ALTR_A10_ECC_INIT_WATCHDOG_10US;
108 
109 	ecc_set_bits(ALTR_A10_ECC_INITA, (ioaddr + ALTR_A10_ECC_CTRL_OFST));
110 	while (limit--) {
111 		if (ecc_test_bits(ALTR_A10_ECC_INITCOMPLETEA,
112 				  (ioaddr + ALTR_A10_ECC_INITSTAT_OFST)))
113 			break;
114 		udelay(1);
115 	}
116 	if (limit < 0)
117 		return -EBUSY;
118 
119 	/* Clear any pending ECC interrupts */
120 	writel(ALTR_A10_ECC_ERRPENA_MASK,
121 	       (ioaddr + ALTR_A10_ECC_INTSTAT_OFST));
122 
123 	return 0;
124 }
125 
126 void socfpga_init_arria10_ocram_ecc(void)
127 {
128 	struct device_node *np;
129 	int ret = 0;
130 	void __iomem *ecc_block_base;
131 
132 	if (!sys_manager_base_addr) {
133 		pr_err("SOCFPGA: sys-mgr is not initialized\n");
134 		return;
135 	}
136 
137 	/* Find the OCRAM EDAC device tree node */
138 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-a10-ocram-ecc");
139 	if (!np) {
140 		pr_err("Unable to find socfpga-a10-ocram-ecc\n");
141 		return;
142 	}
143 
144 	/* Map the ECC Block */
145 	ecc_block_base = of_iomap(np, 0);
146 	of_node_put(np);
147 	if (!ecc_block_base) {
148 		pr_err("Unable to map OCRAM ECC block\n");
149 		return;
150 	}
151 
152 	/* Disable ECC */
153 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
154 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_SET_OFST);
155 	ecc_clear_bits(ALTR_A10_ECC_SERRINTEN,
156 		       (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
157 	ecc_clear_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
158 		       (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
159 
160 	/* Ensure all writes complete */
161 	wmb();
162 
163 	/* Use HW initialization block to initialize memory for ECC */
164 	ret = altr_init_memory_port(ecc_block_base);
165 	if (ret) {
166 		pr_err("ECC: cannot init OCRAM PORTA memory\n");
167 		goto exit;
168 	}
169 
170 	/* Enable ECC */
171 	ecc_set_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
172 		     (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
173 	ecc_set_bits(ALTR_A10_ECC_SERRINTEN,
174 		     (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
175 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
176 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_CLR_OFST);
177 
178 	/* Ensure all writes complete */
179 	wmb();
180 exit:
181 	iounmap(ecc_block_base);
182 }
183