xref: /openbmc/linux/arch/arm/mach-socfpga/ocram.c (revision bb3982b4)
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/genalloc.h>
8 #include <linux/module.h>
9 #include <linux/of_address.h>
10 #include <linux/of_platform.h>
11 
12 #include "core.h"
13 
14 #define ALTR_OCRAM_CLEAR_ECC          0x00000018
15 #define ALTR_OCRAM_ECC_EN             0x00000019
16 
17 void socfpga_init_ocram_ecc(void)
18 {
19 	struct device_node *np;
20 	void __iomem *mapped_ocr_edac_addr;
21 
22 	/* Find the OCRAM EDAC device tree node */
23 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-ocram-ecc");
24 	if (!np) {
25 		pr_err("Unable to find socfpga-ocram-ecc\n");
26 		return;
27 	}
28 
29 	mapped_ocr_edac_addr = of_iomap(np, 0);
30 	of_node_put(np);
31 	if (!mapped_ocr_edac_addr) {
32 		pr_err("Unable to map OCRAM ecc regs.\n");
33 		return;
34 	}
35 
36 	/* Clear any pending OCRAM ECC interrupts, then enable ECC */
37 	writel(ALTR_OCRAM_CLEAR_ECC, mapped_ocr_edac_addr);
38 	writel(ALTR_OCRAM_ECC_EN, mapped_ocr_edac_addr);
39 
40 	iounmap(mapped_ocr_edac_addr);
41 }
42 
43 /* Arria10 OCRAM Section */
44 #define ALTR_A10_ECC_CTRL_OFST          0x08
45 #define ALTR_A10_OCRAM_ECC_EN_CTL       (BIT(1) | BIT(0))
46 #define ALTR_A10_ECC_INITA              BIT(16)
47 
48 #define ALTR_A10_ECC_INITSTAT_OFST      0x0C
49 #define ALTR_A10_ECC_INITCOMPLETEA      BIT(0)
50 #define ALTR_A10_ECC_INITCOMPLETEB      BIT(8)
51 
52 #define ALTR_A10_ECC_ERRINTEN_OFST      0x10
53 #define ALTR_A10_ECC_SERRINTEN          BIT(0)
54 
55 #define ALTR_A10_ECC_INTSTAT_OFST       0x20
56 #define ALTR_A10_ECC_SERRPENA           BIT(0)
57 #define ALTR_A10_ECC_DERRPENA           BIT(8)
58 #define ALTR_A10_ECC_ERRPENA_MASK       (ALTR_A10_ECC_SERRPENA | \
59 					 ALTR_A10_ECC_DERRPENA)
60 /* ECC Manager Defines */
61 #define A10_SYSMGR_ECC_INTMASK_SET_OFST   0x94
62 #define A10_SYSMGR_ECC_INTMASK_CLR_OFST   0x98
63 #define A10_SYSMGR_ECC_INTMASK_OCRAM      BIT(1)
64 
65 #define ALTR_A10_ECC_INIT_WATCHDOG_10US   10000
66 
67 static inline void ecc_set_bits(u32 bit_mask, void __iomem *ioaddr)
68 {
69 	u32 value = readl(ioaddr);
70 
71 	value |= bit_mask;
72 	writel(value, ioaddr);
73 }
74 
75 static inline void ecc_clear_bits(u32 bit_mask, void __iomem *ioaddr)
76 {
77 	u32 value = readl(ioaddr);
78 
79 	value &= ~bit_mask;
80 	writel(value, ioaddr);
81 }
82 
83 static inline int ecc_test_bits(u32 bit_mask, void __iomem *ioaddr)
84 {
85 	u32 value = readl(ioaddr);
86 
87 	return (value & bit_mask) ? 1 : 0;
88 }
89 
90 /*
91  * This function uses the memory initialization block in the Arria10 ECC
92  * controller to initialize/clear the entire memory data and ECC data.
93  */
94 static int altr_init_memory_port(void __iomem *ioaddr)
95 {
96 	int limit = ALTR_A10_ECC_INIT_WATCHDOG_10US;
97 
98 	ecc_set_bits(ALTR_A10_ECC_INITA, (ioaddr + ALTR_A10_ECC_CTRL_OFST));
99 	while (limit--) {
100 		if (ecc_test_bits(ALTR_A10_ECC_INITCOMPLETEA,
101 				  (ioaddr + ALTR_A10_ECC_INITSTAT_OFST)))
102 			break;
103 		udelay(1);
104 	}
105 	if (limit < 0)
106 		return -EBUSY;
107 
108 	/* Clear any pending ECC interrupts */
109 	writel(ALTR_A10_ECC_ERRPENA_MASK,
110 	       (ioaddr + ALTR_A10_ECC_INTSTAT_OFST));
111 
112 	return 0;
113 }
114 
115 void socfpga_init_arria10_ocram_ecc(void)
116 {
117 	struct device_node *np;
118 	int ret = 0;
119 	void __iomem *ecc_block_base;
120 
121 	if (!sys_manager_base_addr) {
122 		pr_err("SOCFPGA: sys-mgr is not initialized\n");
123 		return;
124 	}
125 
126 	/* Find the OCRAM EDAC device tree node */
127 	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-a10-ocram-ecc");
128 	if (!np) {
129 		pr_err("Unable to find socfpga-a10-ocram-ecc\n");
130 		return;
131 	}
132 
133 	/* Map the ECC Block */
134 	ecc_block_base = of_iomap(np, 0);
135 	of_node_put(np);
136 	if (!ecc_block_base) {
137 		pr_err("Unable to map OCRAM ECC block\n");
138 		return;
139 	}
140 
141 	/* Disable ECC */
142 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
143 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_SET_OFST);
144 	ecc_clear_bits(ALTR_A10_ECC_SERRINTEN,
145 		       (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
146 	ecc_clear_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
147 		       (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
148 
149 	/* Ensure all writes complete */
150 	wmb();
151 
152 	/* Use HW initialization block to initialize memory for ECC */
153 	ret = altr_init_memory_port(ecc_block_base);
154 	if (ret) {
155 		pr_err("ECC: cannot init OCRAM PORTA memory\n");
156 		goto exit;
157 	}
158 
159 	/* Enable ECC */
160 	ecc_set_bits(ALTR_A10_OCRAM_ECC_EN_CTL,
161 		     (ecc_block_base + ALTR_A10_ECC_CTRL_OFST));
162 	ecc_set_bits(ALTR_A10_ECC_SERRINTEN,
163 		     (ecc_block_base + ALTR_A10_ECC_ERRINTEN_OFST));
164 	writel(ALTR_A10_OCRAM_ECC_EN_CTL,
165 	       sys_manager_base_addr + A10_SYSMGR_ECC_INTMASK_CLR_OFST);
166 
167 	/* Ensure all writes complete */
168 	wmb();
169 exit:
170 	iounmap(ecc_block_base);
171 }
172