xref: /openbmc/u-boot/post/cpu/mpc83xx/ecc.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2010
4  * Eastman Kodak Company, <www.kodak.com>
5  * Michael Zaidman, <michael.zaidman@kodak.com>
6  *
7  * The code is based on the cpu/mpc83xx/ecc.c written by
8  * Dave Liu <daveliu@freescale.com>
9  */
10 
11 #include <common.h>
12 #include <mpc83xx.h>
13 #include <watchdog.h>
14 #include <asm/io.h>
15 #include <post.h>
16 
17 #if CONFIG_POST & CONFIG_SYS_POST_ECC
18 /*
19  * We use the RAW I/O accessors where possible in order to
20  * achieve performance goal, since the test's execution time
21  * affects the board start up time.
22  */
23 static inline void ecc_clear(ddr83xx_t *ddr)
24 {
25 	/* Clear capture registers */
26 	__raw_writel(0, &ddr->capture_address);
27 	__raw_writel(0, &ddr->capture_data_hi);
28 	__raw_writel(0, &ddr->capture_data_lo);
29 	__raw_writel(0, &ddr->capture_ecc);
30 	__raw_writel(0, &ddr->capture_attributes);
31 
32 	/* Clear SBEC and set SBET to 1 */
33 	out_be32(&ddr->err_sbe, 1 << ECC_ERROR_MAN_SBET_SHIFT);
34 
35 	/* Clear Error Detect register */
36 	out_be32(&ddr->err_detect, ECC_ERROR_DETECT_MME |\
37 			ECC_ERROR_DETECT_MBE |\
38 			ECC_ERROR_DETECT_SBE |\
39 			ECC_ERROR_DETECT_MSE);
40 
41 	isync();
42 }
43 
44 int ecc_post_test(int flags)
45 {
46 	int ret = 0;
47 	int int_state;
48 	int errbit;
49 	u32 pattern[2], writeback[2], retval[2];
50 	ddr83xx_t *ddr = &((immap_t *)CONFIG_SYS_IMMR)->ddr;
51 	volatile u64 *addr = (u64 *)CONFIG_SYS_POST_ECC_START_ADDR;
52 
53 	/* The pattern is written into memory to generate error */
54 	pattern[0] = 0xfedcba98UL;
55 	pattern[1] = 0x76543210UL;
56 
57 	/* After injecting error, re-initialize the memory with the value */
58 	writeback[0] = ~pattern[0];
59 	writeback[1] = ~pattern[1];
60 
61 	/* Check if ECC is enabled */
62 	if (__raw_readl(&ddr->err_disable) & ECC_ERROR_ENABLE) {
63 		debug("DDR's ECC is not enabled, skipping the ECC POST.\n");
64 		return 0;
65 	}
66 
67 	int_state = disable_interrupts();
68 	icache_enable();
69 
70 #ifdef CONFIG_DDR_32BIT
71 	/* It seems like no one really uses the CONFIG_DDR_32BIT mode */
72 #error "Add ECC POST support for CONFIG_DDR_32BIT here!"
73 #else
74 	for (addr = (u64*)CONFIG_SYS_POST_ECC_START_ADDR, errbit=0;
75 	     addr < (u64*)CONFIG_SYS_POST_ECC_STOP_ADDR; addr++, errbit++ ) {
76 
77 		WATCHDOG_RESET();
78 
79 		ecc_clear(ddr);
80 
81 		/* Enable error injection */
82 		setbits_be32(&ddr->ecc_err_inject, ECC_ERR_INJECT_EIEN);
83 		sync();
84 		isync();
85 
86 		/* Set bit to be injected */
87 		if (errbit < 32) {
88 			__raw_writel(1 << errbit, &ddr->data_err_inject_lo);
89 			__raw_writel(0, &ddr->data_err_inject_hi);
90 		} else {
91 			__raw_writel(0, &ddr->data_err_inject_lo);
92 			__raw_writel(1<<(errbit-32), &ddr->data_err_inject_hi);
93 		}
94 		sync();
95 		isync();
96 
97 		/* Write memory location injecting SBE */
98 		ppcDWstore((u32*)addr, pattern);
99 		sync();
100 
101 		/* Disable error injection */
102 		clrbits_be32(&ddr->ecc_err_inject, ECC_ERR_INJECT_EIEN);
103 		sync();
104 		isync();
105 
106 		/* Data read should generate SBE */
107 		ppcDWload((u32*)addr, retval);
108 		sync();
109 
110 		if (!(__raw_readl(&ddr->err_detect) & ECC_ERROR_DETECT_SBE) ||
111 			(__raw_readl(&ddr->data_err_inject_hi) !=
112 			(__raw_readl(&ddr->capture_data_hi) ^ pattern[0])) ||
113 			(__raw_readl(&ddr->data_err_inject_lo) !=
114 			(__raw_readl(&ddr->capture_data_lo) ^ pattern[1]))) {
115 
116 			post_log("ECC failed to detect SBE error at %08x, "
117 				"SBE injection mask %08x-%08x, wrote "
118 				"%08x-%08x, read %08x-%08x\n", addr,
119 				ddr->data_err_inject_hi,
120 				ddr->data_err_inject_lo,
121 				pattern[0], pattern[1],
122 				retval[0], retval[1]);
123 
124 			printf("ERR_DETECT Reg: %08x\n", ddr->err_detect);
125 			printf("ECC CAPTURE_DATA Reg: %08x-%08x\n",
126 				ddr->capture_data_hi, ddr->capture_data_lo);
127 			ret = 1;
128 			break;
129 		}
130 
131 		/* Re-initialize the ECC memory */
132 		ppcDWstore((u32*)addr, writeback);
133 		sync();
134 		isync();
135 
136 		errbit %= 63;
137 	}
138 #endif /* !CONFIG_DDR_32BIT */
139 
140 	ecc_clear(ddr);
141 
142 	icache_disable();
143 
144 	if (int_state)
145 		enable_interrupts();
146 
147 	return ret;
148 }
149 #endif
150