[PATCHv3 3/3] edac: altera: Add EDAC support for Altera SDRAM

Borislav Petkov
2014-05-08T12:05:24Z

On Mon, May 05, 2014 at 05:52:17PM -0500, tthayer at altera.com wrote:
> From: Thor Thayer <tthayer@altera.com>

Missing commit message.

> ---
> v2: Use the SDRAM controller registers to calculate memory size
> instead of the Device Tree. Update To & Cc list. Add maintainer
> information.
>
> v3: EDAC driver cleanup based on comments from Mailing list.
>
> Signed-off-by: Thor Thayer <tthayer@altera.com>
> ---
> MAINTAINERS | 5 +
> drivers/edac/Kconfig | 9 +
> drivers/edac/Makefile | 2 +
> drivers/edac/altera_edac.c | 411 ++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 427 insertions(+)
> create mode 100644 drivers/edac/altera_edac.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e67ea24..ecd1277 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1290,6 +1290,11 @@ M: Dinh Nguyen <dinguyen@altera.com>
> S: Maintained
> F: drivers/clk/socfpga/
>
> +ARM/SOCFPGA SDRAM EDAC SUPPORT
> +M: Thor Thayer <tthayer@altera.com>
> +S: Maintained
> +F: drivers/edac/altera_edac.c
> +
> ARM/STI ARCHITECTURE
> M: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
> M: Maxime Coquelin <maxime.coquelin@st.com>
> diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> index 878f090..4f4d379 100644
> --- a/drivers/edac/Kconfig
> +++ b/drivers/edac/Kconfig
> @@ -368,4 +368,13 @@ config EDAC_OCTEON_PCI
> Support for error detection and correction on the
> Cavium Octeon family of SOCs.
>
> +config EDAC_ALTERA_MC
> + bool "Altera SDRAM Memory Controller EDAC"
> + depends on EDAC_MM_EDAC && ARCH_SOCFPGA
> + help
> + Support for error detection and correction on the
> + Altera SDRAM memory controller. Note that the
> + preloader must initialize the SDRAM before loading
> + the kernel.
> +
> endif # EDAC
> diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
> index 4154ed6..9741336 100644
> --- a/drivers/edac/Makefile
> +++ b/drivers/edac/Makefile
> @@ -64,3 +64,5 @@ obj-$(CONFIG_EDAC_OCTEON_PC) += octeon_edac-pc.o
> obj-$(CONFIG_EDAC_OCTEON_L2C) += octeon_edac-l2c.o
> obj-$(CONFIG_EDAC_OCTEON_LMC) += octeon_edac-lmc.o
> obj-$(CONFIG_EDAC_OCTEON_PCI) += octeon_edac-pci.o
> +
> +obj-$(CONFIG_EDAC_ALTERA_MC) += altera_edac.o
> diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> new file mode 100644
> index 0000000..e8a3de7
> --- /dev/null
> +++ b/drivers/edac/altera_edac.c
> @@ -0,0 +1,411 @@
> +/*
> + * Copyright Altera Corporation (C) 2014. All rights reserved.
> + * Copyright 2011-2012 Calxeda, Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> + * more details.
> + *
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License. See the file "COPYING" in the main directory of this archive
> + * for more details.

I'm guessing your lawyers want this boilerplate after all?

...

> +static irqreturn_t altr_sdram_mc_err_handler(int irq, void *dev_id)
> +{
> + struct mem_ctl_info *mci = dev_id;
> + struct altr_sdram_mc_data *drvdata = mci->pvt_info;
> + u32 status = 0, err_count = 0, err_addr = 0;
> +
> + /* Error Address is shared by both SBE & DBE */
> + regmap_read(drvdata->mc_vbase, ERRADDR, &err_addr);
> +
> + regmap_read(drvdata->mc_vbase, DRAMSTS, &status);
> +
> + if (status & DRAMSTS_DBEERR) {
> + regmap_read(drvdata->mc_vbase, DBECOUNT, &err_count);
> + edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, err_count,
> + err_addr >> PAGE_SHIFT,
> + err_addr & ~PAGE_MASK, 0,
> + 0, 0, -1, mci->ctl_name, "");

So, are we setting edac_mc_panic_on_ue now or what are we planning to do
for uncorrectable errors?

> + if (status & DRAMSTS_SBEERR) {
> + regmap_read(drvdata->mc_vbase, SBECOUNT, &err_count);
> + edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, err_count,
> + err_addr >> PAGE_SHIFT,
> + err_addr & ~PAGE_MASK, 0,
> + 0, 0, -1, mci->ctl_name, "");
> + }
> +
> + regmap_write(drvdata->mc_vbase, DRAMINTR,
> + (DRAMINTR_INTRCLR | DRAMINTR_INTREN));
> +
> + return IRQ_HANDLED;
> +}
> +
> +#ifdef CONFIG_EDAC_DEBUG
> +static ssize_t altr_sdr_mc_err_inject_write(struct file *file,
> + const char __user *data,
> + size_t count, loff_t *ppos)
> +{
> + struct mem_ctl_info *mci = file->private_data;
> + struct altr_sdram_mc_data *drvdata = mci->pvt_info;
> + u32 *ptemp;
> + dma_addr_t dma_handle;
> + u32 reg, read_reg = 0;
> +
> + ptemp = dma_alloc_coherent(mci->pdev, 16, &dma_handle, GFP_KERNEL);
> + if (IS_ERR(ptemp)) {
> + dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);
> + edac_printk(KERN_ERR, EDAC_MC,
> + "EDAC Inject: Buffer Allocation error\n");
> + return -ENOMEM;
> + }
> +
> + regmap_read(drvdata->mc_vbase, CTLCFG, &read_reg);
> + read_reg &= ~(CTLCFG_GEN_SB_ERR | CTLCFG_GEN_DB_ERR);
> +
> + if (count == 3) {
> + edac_printk(KERN_ALERT, EDAC_MC,
> + "EDAC Inject Double bit error\n");
> + regmap_write(drvdata->mc_vbase, CTLCFG,
> + (read_reg | CTLCFG_GEN_DB_ERR));
> + } else {
> + edac_printk(KERN_ALERT, EDAC_MC,
> + "EDAC Inject Single bit error\n");
> + regmap_write(drvdata->mc_vbase, CTLCFG,
> + (read_reg | CTLCFG_GEN_SB_ERR));

You can remove the "EDAC " string from those printks above as
edac_printk already adds the prefix.

> + }
> +
> + ptemp[0] = 0x5A5A5A5A;
> + ptemp[1] = 0xA5A5A5A5;
> + regmap_write(drvdata->mc_vbase, CTLCFG, read_reg);
> + /* Ensure it has been written out */
> + wmb();
> +
> + reg = ptemp[0];
> + read_reg = ptemp[1];
> + /* Force Read */
> + rmb();

Have you checked whether those reads don't get optimized away by the
compiler? I know, you need them for triggering the error condition.

Also, you should add a comment here to explain why the reads are being
done.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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