xref: /openbmc/linux/arch/arm/mach-socfpga/ocram.c (revision 6db6b729)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright Altera Corporation (C) 2016. All rights reserved.
4  */
5 #include <linux/delay.h>
6 #include <linux/io.h>
7 #include <linux/of.h>
8 #include <linux/of_address.h>
9 
10 #include "core.h"
11 
12 #define ALTR_OCRAM_CLEAR_ECC          0x00000018
13 #define ALTR_OCRAM_ECC_EN             0x00000019
14 
15 void socfpga_init_ocram_ecc(void)
16 {
17 	struct device_node *np;
18 	void __iomem *mapped_ocr_edac_addr;
19 
20 	/* Find the OCRAM EDAC device tree node */
21 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-ocram-ecc");
22 	if (!np) {
23 		pr_err("Unable to find socfpga-ocram-ecc\n");
24 		return;
25 	}
26 
27 	mapped_ocr_edac_addr = of_iomap(np, 0);
28 	of_node_put(np);
29 	if (!mapped_ocr_edac_addr) {
30 		pr_err("Unable to map OCRAM ecc regs.\n");
31 		return;
32 	}
33 
34 	/* Clear any pending OCRAM ECC interrupts, then enable ECC */
35 	writel(ALTR_OCRAM_CLEAR_ECC, mapped_ocr_edac_addr);
36 	writel(ALTR_OCRAM_ECC_EN, mapped_ocr_edac_addr);
37 
38 	iounmap(mapped_ocr_edac_addr);
39 }
40 
41 /* Arria10 OCRAM Section */
42 #define ALTR_A10_ECC_CTRL_OFST          0x08
43 #define ALTR_A10_OCRAM_ECC_EN_CTL       (BIT(1) | BIT(0))
44 #define ALTR_A10_ECC_INITA              BIT(16)
45 
46 #define ALTR_A10_ECC_INITSTAT_OFST      0x0C
47 #define ALTR_A10_ECC_INITCOMPLETEA      BIT(0)
48 #define ALTR_A10_ECC_INITCOMPLETEB      BIT(8)
49 
50 #define ALTR_A10_ECC_ERRINTEN_OFST      0x10
51 #define ALTR_A10_ECC_SERRINTEN          BIT(0)
52 
53 #define ALTR_A10_ECC_INTSTAT_OFST       0x20
54 #define ALTR_A10_ECC_SERRPENA           BIT(0)
55 #define ALTR_A10_ECC_DERRPENA           BIT(8)
56 #define ALTR_A10_ECC_ERRPENA_MASK       (ALTR_A10_ECC_SERRPENA | \
57 					 ALTR_A10_ECC_DERRPENA)
58 /* ECC Manager Defines */
59 #define A10_SYSMGR_ECC_INTMASK_SET_OFST   0x94
60 #define A10_SYSMGR_ECC_INTMASK_CLR_OFST   0x98
61 #define A10_SYSMGR_ECC_INTMASK_OCRAM      BIT(1)
62 
63 #define ALTR_A10_ECC_INIT_WATCHDOG_10US   10000
64 
65 static inline void ecc_set_bits(u32 bit_mask, void __iomem *ioaddr)
66 {
67 	u32 value = readl(ioaddr);
68 
69 	value |= bit_mask;
70 	writel(value, ioaddr);
71 }
72 
73 static inline void ecc_clear_bits(u32 bit_mask, void __iomem *ioaddr)
74 {
75 	u32 value = readl(ioaddr);
76 
77 	value &= ~bit_mask;
78 	writel(value, ioaddr);
79 }
80 
81 static inline int ecc_test_bits(u32 bit_mask, void __iomem *ioaddr)
82 {
83 	u32 value = readl(ioaddr);
84 
85 	return (value & bit_mask) ? 1 : 0;
86 }
87 
88 /*
89  * This function uses the memory initialization block in the Arria10 ECC
90  * controller to initialize/clear the entire memory data and ECC data.
91  */
92 static int altr_init_memory_port(void __iomem *ioaddr)
93 {
94 	int limit = ALTR_A10_ECC_INIT_WATCHDOG_10US;
95 
96 	ecc_set_bits(ALTR_A10_ECC_INITA, (ioaddr + ALTR_A10_ECC_CTRL_OFST));
97 	while (limit--) {
98 		if (ecc_test_bits(ALTR_A10_ECC_INITCOMPLETEA,
99 				  (ioaddr + ALTR_A10_ECC_INITSTAT_OFST)))
100 			break;
101 		udelay(1);
102 	}
103 	if (limit < 0)
104 		return -EBUSY;
105 
106 	/* Clear any pending ECC interrupts */
107 	writel(ALTR_A10_ECC_ERRPENA_MASK,
108 	       (ioaddr + ALTR_A10_ECC_INTSTAT_OFST));
109 
110 	return 0;
111 }
112 
113 void socfpga_init_arria10_ocram_ecc(void)
114 {
115 	struct device_node *np;
116 	int ret = 0;
117 	void __iomem *ecc_block_base;
118 
119 	if (!sys_manager_base_addr) {
120 		pr_err("SOCFPGA: sys-mgr is not initialized\n");
121 		return;
122 	}
123 
124 	/* Find the OCRAM EDAC device tree node */
125 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-a10-ocram-ecc");
126 	if (!np) {
127 		pr_err("Unable to find socfpga-a10-ocram-ecc\n");
128 		return;
129 	}
130 
131 	/* Map the ECC Block */
132 	ecc_block_base = of_iomap(np, 0);
133 	of_node_put(np);
134 	if (!ecc_block_base) {
135 		pr_err("Unable to map OCRAM ECC block\n");
136 		return;
137 	}
138 
139 	/* Disable ECC */
140 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
141 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_SET_OFST);
142 	ecc_clear_bits(ALTR_A10_ECC_SERRINTEN,
143 		       (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
144 	ecc_clear_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
145 		       (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
146 
147 	/* Ensure all writes complete */
148 	wmb();
149 
150 	/* Use HW initialization block to initialize memory for ECC */
151 	ret = altr_init_memory_port(ecc_block_base);
152 	if (ret) {
153 		pr_err("ECC: cannot init OCRAM PORTA memory\n");
154 		goto exit;
155 	}
156 
157 	/* Enable ECC */
158 	ecc_set_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
159 		     (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
160 	ecc_set_bits(ALTR_A10_ECC_SERRINTEN,
161 		     (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
162 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
163 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_CLR_OFST);
164 
165 	/* Ensure all writes complete */
166 	wmb();
167 exit:
168 	iounmap(ecc_block_base);
169 }
170