diff options
Diffstat (limited to 'drivers/edac/altera_edac.c')
| -rw-r--r-- | drivers/edac/altera_edac.c | 40 |
1 files changed, 39 insertions, 1 deletions
diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c index 5dd29789f97d..e7e8e624a436 100644 --- a/drivers/edac/altera_edac.c +++ b/drivers/edac/altera_edac.c @@ -1083,8 +1083,46 @@ static int __init __maybe_unused altr_init_a10_ecc_device_type(char *compat) #ifdef CONFIG_EDAC_ALTERA_SDRAM +/* + * A legacy U-Boot bug only enabled memory mapped access to the ECC Enable + * register if ECC is enabled. Linux checks the ECC Enable register to + * determine ECC status. + * Use an SMC call (which always works) to determine ECC enablement. + */ +static int altr_s10_sdram_check_ecc_deps(struct altr_edac_device_dev *device) +{ + const struct edac_device_prv_data *prv = device->data; + unsigned long sdram_ecc_addr; + struct arm_smccc_res result; + struct device_node *np; + phys_addr_t sdram_addr; + u32 read_reg; + int ret; + + np = of_find_compatible_node(NULL, NULL, "altr,sdr-ctl"); + if (!np) + goto sdram_err; + + sdram_addr = of_translate_address(np, of_get_address(np, 0, + NULL, NULL)); + of_node_put(np); + sdram_ecc_addr = (unsigned long)sdram_addr + prv->ecc_en_ofst; + arm_smccc_smc(INTEL_SIP_SMC_REG_READ, sdram_ecc_addr, + 0, 0, 0, 0, 0, 0, &result); + read_reg = (unsigned int)result.a1; + ret = (int)result.a0; + if (!ret && (read_reg & prv->ecc_enable_mask)) + return 0; + +sdram_err: + edac_printk(KERN_ERR, EDAC_DEVICE, + "%s: No ECC present or ECC disabled.\n", + device->edac_dev_name); + return -ENODEV; +} + static const struct edac_device_prv_data s10_sdramecc_data = { - .setup = altr_check_ecc_deps, + .setup = altr_s10_sdram_check_ecc_deps, .ce_clear_mask = ALTR_S10_ECC_SERRPENA, .ue_clear_mask = ALTR_S10_ECC_DERRPENA, .ecc_enable_mask = ALTR_S10_ECC_EN, |