xref: /openbmc/u-boot/post/cpu/mpc83xx/ecc.c (revision 23ff8633)
1 /*
2  * (C) Copyright 2010
3  * Eastman Kodak Company, <www.kodak.com>
4  * Michael Zaidman, <michael.zaidman@kodak.com>
5  *
6  * The code is based on the cpu/mpc83xx/ecc.c written by
7  * Dave Liu <daveliu@freescale.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <mpc83xx.h>
14 #include <watchdog.h>
15 #include <asm/io.h>
16 #include <post.h>
17 
18 #if CONFIG_POST & CONFIG_SYS_POST_ECC
19 /*
20  * We use the RAW I/O accessors where possible in order to
21  * achieve performance goal, since the test's execution time
22  * affects the board start up time.
23  */
24 static inline void ecc_clear(ddr83xx_t *ddr)
25 {
26 	/* Clear capture registers */
27 	__raw_writel(0, &ddr->capture_address);
28 	__raw_writel(0, &ddr->capture_data_hi);
29 	__raw_writel(0, &ddr->capture_data_lo);
30 	__raw_writel(0, &ddr->capture_ecc);
31 	__raw_writel(0, &ddr->capture_attributes);
32 
33 	/* Clear SBEC and set SBET to 1 */
34 	out_be32(&ddr->err_sbe, 1 << ECC_ERROR_MAN_SBET_SHIFT);
35 
36 	/* Clear Error Detect register */
37 	out_be32(&ddr->err_detect, ECC_ERROR_DETECT_MME |\
38 			ECC_ERROR_DETECT_MBE |\
39 			ECC_ERROR_DETECT_SBE |\
40 			ECC_ERROR_DETECT_MSE);
41 
42 	isync();
43 }
44 
45 int ecc_post_test(int flags)
46 {
47 	int ret = 0;
48 	int int_state;
49 	int errbit;
50 	u32 pattern[2], writeback[2], retval[2];
51 	ddr83xx_t *ddr = &((immap_t *)CONFIG_SYS_IMMR)->ddr;
52 	volatile u64 *addr = (u64 *)CONFIG_SYS_POST_ECC_START_ADDR;
53 
54 	/* The pattern is written into memory to generate error */
55 	pattern[0] = 0xfedcba98UL;
56 	pattern[1] = 0x76543210UL;
57 
58 	/* After injecting error, re-initialize the memory with the value */
59 	writeback[0] = ~pattern[0];
60 	writeback[1] = ~pattern[1];
61 
62 	/* Check if ECC is enabled */
63 	if (__raw_readl(&ddr->err_disable) & ECC_ERROR_ENABLE) {
64 		debug("DDR's ECC is not enabled, skipping the ECC POST.\n");
65 		return 0;
66 	}
67 
68 	int_state = disable_interrupts();
69 	icache_enable();
70 
71 #ifdef CONFIG_DDR_32BIT
72 	/* It seems like no one really uses the CONFIG_DDR_32BIT mode */
73 #error "Add ECC POST support for CONFIG_DDR_32BIT here!"
74 #else
75 	for (addr = (u64*)CONFIG_SYS_POST_ECC_START_ADDR, errbit=0;
76 	     addr < (u64*)CONFIG_SYS_POST_ECC_STOP_ADDR; addr++, errbit++ ) {
77 
78 		WATCHDOG_RESET();
79 
80 		ecc_clear(ddr);
81 
82 		/* Enable error injection */
83 		setbits_be32(&ddr->ecc_err_inject, ECC_ERR_INJECT_EIEN);
84 		sync();
85 		isync();
86 
87 		/* Set bit to be injected */
88 		if (errbit < 32) {
89 			__raw_writel(1 << errbit, &ddr->data_err_inject_lo);
90 			__raw_writel(0, &ddr->data_err_inject_hi);
91 		} else {
92 			__raw_writel(0, &ddr->data_err_inject_lo);
93 			__raw_writel(1<<(errbit-32), &ddr->data_err_inject_hi);
94 		}
95 		sync();
96 		isync();
97 
98 		/* Write memory location injecting SBE */
99 		ppcDWstore((u32*)addr, pattern);
100 		sync();
101 
102 		/* Disable error injection */
103 		clrbits_be32(&ddr->ecc_err_inject, ECC_ERR_INJECT_EIEN);
104 		sync();
105 		isync();
106 
107 		/* Data read should generate SBE */
108 		ppcDWload((u32*)addr, retval);
109 		sync();
110 
111 		if (!(__raw_readl(&ddr->err_detect) & ECC_ERROR_DETECT_SBE) ||
112 			(__raw_readl(&ddr->data_err_inject_hi) !=
113 			(__raw_readl(&ddr->capture_data_hi) ^ pattern[0])) ||
114 			(__raw_readl(&ddr->data_err_inject_lo) !=
115 			(__raw_readl(&ddr->capture_data_lo) ^ pattern[1]))) {
116 
117 			post_log("ECC failed to detect SBE error at %08x, "
118 				"SBE injection mask %08x-%08x, wrote "
119 				"%08x-%08x, read %08x-%08x\n", addr,
120 				ddr->data_err_inject_hi,
121 				ddr->data_err_inject_lo,
122 				pattern[0], pattern[1],
123 				retval[0], retval[1]);
124 
125 			printf("ERR_DETECT Reg: %08x\n", ddr->err_detect);
126 			printf("ECC CAPTURE_DATA Reg: %08x-%08x\n",
127 				ddr->capture_data_hi, ddr->capture_data_lo);
128 			ret = 1;
129 			break;
130 		}
131 
132 		/* Re-initialize the ECC memory */
133 		ppcDWstore((u32*)addr, writeback);
134 		sync();
135 		isync();
136 
137 		errbit %= 63;
138 	}
139 #endif /* !CONFIG_DDR_32BIT */
140 
141 	ecc_clear(ddr);
142 
143 	icache_disable();
144 
145 	if (int_state)
146 		enable_interrupts();
147 
148 	return ret;
149 }
150 #endif
151