Re: [PATCH v5 2/2] edac: zynqmp_ocm: Add EDAC support for ZynqMP OCM

From: Borislav Petkov
Date: Thu Sep 29 2022 - 11:56:14 EST


On Fri, Sep 09, 2022 at 11:35:48AM +0530, Sai Krishna Potthuri wrote:
> Subject: Re: [PATCH v5 2/2] edac: zynqmp_ocm: Add EDAC support for ZynqMP OCM

"EDAC/zynqmp: Add ..."

> Add EDAC support for Xilinx ZynqMP OCM Controller, this driver
> reports CE and UE errors based on the interrupts,

Based on the interrupts? Do you mean, it raises an interrupt in order to
report errors vs polling?

> and also creates ue/ce

s/ue/UE/g
s/ce/CE/g

> sysfs entries for error injection.

All the injection logic needs to be behind CONFIG_EDAC_DEBUG. You don't
want to have injection functionality present in production.

> Co-developed-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxx>
> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxx>
> Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri@xxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> ---
> MAINTAINERS | 7 +
> drivers/edac/Kconfig | 9 +
> drivers/edac/Makefile | 1 +
> drivers/edac/zynqmp_ocm_edac.c | 622 +++++++++++++++++++++++++++++++++
> 4 files changed, 639 insertions(+)
> create mode 100644 drivers/edac/zynqmp_ocm_edac.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index edc96cdb85e8..7a40caf536c2 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -21692,6 +21692,13 @@ F: Documentation/devicetree/bindings/dma/xilinx/xlnx,zynqmp-dpdma.yaml
> F: drivers/dma/xilinx/xilinx_dpdma.c
> F: include/dt-bindings/dma/xlnx-zynqmp-dpdma.h
>
> +XILINX ZYNQMP OCM EDAC DRIVER
> +M: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxx>
> +M: Sai Krishna Potthuri <sai.krishna.potthuri@xxxxxxx>
> +S: Maintained
> +F: Documentation/devicetree/bindings/memory-controllers/xlnx,zynqmp-ocmc-1.0.yaml
> +F: drivers/edac/zynqmp_ocm_edac.c
> +
> XILINX ZYNQMP PSGTR PHY DRIVER
> M: Anurag Kumar Vulisha <anurag.kumar.vulisha@xxxxxxxxxx>
> M: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> index 58ab63642e72..bc30b7d02062 100644
> --- a/drivers/edac/Kconfig
> +++ b/drivers/edac/Kconfig
> @@ -539,4 +539,13 @@ config EDAC_DMC520
> Support for error detection and correction on the
> SoCs with ARM DMC-520 DRAM controller.
>
> +config EDAC_ZYNQMP_OCM
> + tristate "Xilinx ZynqMP OCM Controller"
> + depends on ARCH_ZYNQMP || COMPILE_TEST
> + help
> + This driver is targeted for Xilinx ZynqMP OCM (On Chip Memory)
> + controller to support for error detection and correction.
> + This driver can also be built as a module. If so, the module
> + will be called zynqmp_ocm_edac.
> +
> endif # EDAC
> diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
> index 2d1641a27a28..634c1cec1588 100644
> --- a/drivers/edac/Makefile
> +++ b/drivers/edac/Makefile
> @@ -84,3 +84,4 @@ obj-$(CONFIG_EDAC_QCOM) += qcom_edac.o
> obj-$(CONFIG_EDAC_ASPEED) += aspeed_edac.o
> obj-$(CONFIG_EDAC_BLUEFIELD) += bluefield_edac.o
> obj-$(CONFIG_EDAC_DMC520) += dmc520_edac.o
> +obj-$(CONFIG_EDAC_ZYNQMP_OCM) += zynqmp_ocm_edac.o
> diff --git a/drivers/edac/zynqmp_ocm_edac.c b/drivers/edac/zynqmp_ocm_edac.c
> new file mode 100644
> index 000000000000..a8da94f3e067
> --- /dev/null
> +++ b/drivers/edac/zynqmp_ocm_edac.c
> @@ -0,0 +1,622 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Xilinx ZynqMP OCM ECC Driver
> + *
> + * Copyright (C) 2022 Advanced Micro Devices, Inc.
> + */
> +
> +#include <linux/edac.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +
> +#include "edac_module.h"
> +
> +#define ZYNQMP_OCM_EDAC_MSG_SIZE 256
> +
> +#define ZYNQMP_OCM_EDAC_STRING "zynqmp_ocm"
> +
> +/* Controller registers */
> +#define CTRL_OFST 0x0
> +#define OCM_ISR_OFST 0x04
> +#define OCM_IMR_OFST 0x08
> +#define OCM_IEN_OFST 0x0C
> +#define OCM_IDS_OFST 0x10
> +
> +/* ECC control register */
> +#define ECC_CTRL_OFST 0x14
> +
> +/* Correctable error info registers */
> +#define CE_FFA_OFST 0x1C
> +#define CE_FFD0_OFST 0x20
> +#define CE_FFD1_OFST 0x24
> +#define CE_FFD2_OFST 0x28
> +#define CE_FFD3_OFST 0x2C
> +#define CE_FFE_OFST 0x30
> +
> +/* Uncorrectable error info registers */
> +#define UE_FFA_OFST 0x34
> +#define UE_FFD0_OFST 0x38
> +#define UE_FFD1_OFST 0x3C
> +#define UE_FFD2_OFST 0x40
> +#define UE_FFD3_OFST 0x44
> +#define UE_FFE_OFST 0x48
> +
> +/* ECC control register bit field definitions */
> +#define ECC_CTRL_CLR_CE_ERR 0x40
> +#define ECC_CTRL_CLR_UE_ERR 0x80
> +
> +/* Fault injection data and count registers */
> +#define OCM_FID0_OFST 0x4C
> +#define OCM_FID1_OFST 0x50
> +#define OCM_FID2_OFST 0x54
> +#define OCM_FID3_OFST 0x58
> +#define OCM_FIC_OFST 0x74
> +
> +#define UE_MAX_BITPOS_LOWER 31
> +#define UE_MIN_BITPOS_UPPER 32
> +#define UE_MAX_BITPOS_UPPER 63
> +
> +/* Interrupt masks */
> +#define OCM_CEINTR_MASK BIT(6)
> +#define OCM_UEINTR_MASK BIT(7)
> +#define OCM_ECC_ENABLE_MASK BIT(0)
> +#define OCM_CEUE_MASK GENMASK(7, 6)
> +
> +#define OCM_FICOUNT_MASK GENMASK(23, 0)
> +#define OCM_BASEVAL 0xFFFC0000
> +#define EDAC_DEVICE "ZynqMP-OCM"

Align those vertically properly.

> +
> +/**
> + * struct ecc_error_info - ECC error log information
> + * @addr: Fault generated at this address
> + * @data0: Generated fault data
> + * @data1: Generated fault data

What's the difference?

> + */
> +struct ecc_error_info {
> + u32 addr;
> + u32 data0;
> + u32 data1;
> +};
> +
> +/**
> + * struct zynqmp_ocm_ecc_status - ECC status information to report
> + * @ce_cnt: Correctable error count
> + * @ue_cnt: Uncorrectable error count
> + * @ceinfo: Correctable error log information
> + * @ueinfo: Uncorrectable error log information
> + */
> +struct zynqmp_ocm_ecc_status {
> + u32 ce_cnt;
> + u32 ue_cnt;
> + struct ecc_error_info ceinfo;
> + struct ecc_error_info ueinfo;
> +};
> +
> +/**
> + * struct zynqmp_ocm_edac_priv - DDR memory controller private instance data
> + * @baseaddr: Base address of the DDR controller
> + * @message: Buffer for framing the event specific info
> + * @stat: ECC status information
> + * @p_data: Pointer to platform data
> + * @ce_cnt: Correctable Error count
> + * @ue_cnt: Uncorrectable Error count
> + * @ce_bitpos: Bit position for Correctable Error
> + * @ue_bitpos0: First bit position for Uncorrectable Error
> + * @ue_bitpos1: Second bit position for Uncorrectable Error
> + */
> +struct zynqmp_ocm_edac_priv {

Why do those structs have a "zynqmp_ocm_" prefix if they're going to be
used only in this driver?

> + void __iomem *baseaddr;
> + char message[ZYNQMP_OCM_EDAC_MSG_SIZE];
> + struct zynqmp_ocm_ecc_status stat;
> + const struct zynqmp_ocm_platform_data *p_data;
> + u32 ce_cnt;
> + u32 ue_cnt;
> + u8 ce_bitpos;
> + u8 ue_bitpos0;
> + u8 ue_bitpos1;
> +};
> +
> +/**
> + * zynqmp_ocm_edac_geterror_info - Get the current ecc error info

s/ecc/ECC/g

> + * @base: Pointer to the base address of the ddr memory controller

s/ddr/DDR/g

> + * @p: Pointer to the ocm ecc status structure
> + * @mask: Status register mask value
> + *
> + * Determines there is any ecc error or not
> + *
> + */
> +static void zynqmp_ocm_edac_geterror_info(void __iomem *base,
> + struct zynqmp_ocm_ecc_status *p, int mask)

Drop the "zynqmp_ocm_edac_" prefix from all static functions. That's
just useless naming. And it is a lot more readable this way:

static void get_error_info(void __iomem *base, struct ecc_status *p, int mask)
{
...

nice and simple.

> +{
> + if (mask & OCM_CEINTR_MASK) {
> + p->ce_cnt++;
> + p->ceinfo.data0 = readl(base + CE_FFD0_OFST);
> + p->ceinfo.data1 = readl(base + CE_FFD1_OFST);
> + p->ceinfo.addr = (OCM_BASEVAL | readl(base + CE_FFA_OFST));
> + writel(ECC_CTRL_CLR_CE_ERR, base + OCM_ISR_OFST);
> + } else if (mask & OCM_UEINTR_MASK) {
> + p->ue_cnt++;
> + p->ueinfo.data0 = readl(base + UE_FFD0_OFST);
> + p->ueinfo.data1 = readl(base + UE_FFD1_OFST);
> + p->ueinfo.addr = (OCM_BASEVAL | readl(base + UE_FFA_OFST));
> + writel(ECC_CTRL_CLR_UE_ERR, base + OCM_ISR_OFST);
> + }

else {
WARN_ON_ONCE(...);
}

or does the hardware always give a correct mask?

:)

> +}
> +
> +/**
> + * zynqmp_ocm_edac_handle_error - Handle controller error types CE and UE
> + * @dci: Pointer to the edac device controller instance
> + * @p: Pointer to the ocm ecc status structure
> + *
> + * Handles the controller ECC correctable and uncorrectable error.
> + */
> +static void zynqmp_ocm_edac_handle_error(struct edac_device_ctl_info *dci,
> + struct zynqmp_ocm_ecc_status *p)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> + struct ecc_error_info *pinf;
> +
> + if (p->ce_cnt) {
> + pinf = &p->ceinfo;
> + snprintf(priv->message, ZYNQMP_OCM_EDAC_MSG_SIZE,
> + "\nOCM ECC error type :%s\n"
> + "Addr: [0x%X]\nFault Data[31:0]: [0x%X]\n"
> + "Fault Data[63:32]: [0x%X]",

Do not break the strings in lines for easier grepping. IOW:

"OCM ECC error type :%s Addr: [0x%X] Fault Data[31:0]: [0x%X] Fault Data[63:32]: [0x%X]\n"

And you can do:

"... Fault Data[0x%08x%08x]\n",
pinf->data1, pinf->data0);

and dump the whole 64-bit value.

> + "CE", pinf->addr, pinf->data0, pinf->data1);
> + edac_device_handle_ce(dci, 0, 0, priv->message);
> + }
> +
> + if (p->ue_cnt) {
> + pinf = &p->ueinfo;
> + snprintf(priv->message, ZYNQMP_OCM_EDAC_MSG_SIZE,
> + "\nOCM ECC error type :%s\n"
> + "Addr: [0x%X]\nFault Data[31:0]: [0x%X]\n"
> + "Fault Data[63:32]: [0x%X]",
> + "UE", pinf->addr, pinf->data0, pinf->data1);

Ditto.

> + edac_device_handle_ue(dci, 0, 0, priv->message);
> + }
> +
> + memset(p, 0, sizeof(*p));
> +}
> +
> +/**
> + * zynqmp_ocm_edac_intr_handler - isr routine

s/isr/ISR/

> + * @irq: irq number
> + * @dev_id: device id pointer
> + *
> + * This is the ISR routine called by edac core interrupt thread.

This is simply not true.

Also,

s/edac/EDAC/g

You get the idea - all acronyms in all-caps.

> + * Used to check and post ECC errors.
> + *
> + * Return: IRQ_NONE, if interrupt not set or IRQ_HANDLED otherwise
> + */
> +static irqreturn_t zynqmp_ocm_edac_intr_handler(int irq, void *dev_id)
> +{
> + struct edac_device_ctl_info *dci = dev_id;
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> + int regval;
> +
> + regval = readl(priv->baseaddr + OCM_ISR_OFST);
> + if (!(regval & OCM_CEUE_MASK))
> + return IRQ_NONE;
> +
> + zynqmp_ocm_edac_geterror_info(priv->baseaddr,
> + &priv->stat, regval);

No need to break that line.

> +
> + priv->ce_cnt += priv->stat.ce_cnt;
> + priv->ue_cnt += priv->stat.ue_cnt;
> + zynqmp_ocm_edac_handle_error(dci, &priv->stat);
> +
> + return IRQ_HANDLED;
> +}
> +
> +/**
> + * zynqmp_ocm_edac_get_eccstate - Return the controller ecc status
> + * @base: Pointer to the ddr memory controller base address
> + *
> + * Get the ECC enable/disable status for the controller
> + *
> + * Return: ecc status 0/1.
> + */
> +static bool zynqmp_ocm_edac_get_eccstate(void __iomem *base)
> +{
> + return readl(base + ECC_CTRL_OFST) & OCM_ECC_ENABLE_MASK;
> +}

As already mentioned

#ifdef CONFIG_EDAC_DEBUG

...

> +
> +/**
> + * zynqmp_ocm_edac_inject_fault_count_show - Shows fault injection count
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + *
> + * Shows the fault injection count, once the counter reaches
> + * zero, it injects errors
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_fault_count_show(struct edac_device_ctl_info *dci,
> + char *data)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + return sprintf(data, "FIC: 0x%x\n",

"FIC"?

Maybe make it human readable:

"Fault injection count: "

> + readl(priv->baseaddr + OCM_FIC_OFST));
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_fault_count_store - write fi count
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + * @count: read the size bytes from buffer
> + *
> + * Update the fault injection count register, once the counter reaches
> + * zero, it injects errors

How does the counter reach zero?

I guess I'm unclear on how this is supposed to be used: you write some
fault injection count value and what happens then?

> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_fault_count_store(struct edac_device_ctl_info *dci,
> + const char *data, size_t count)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> + u32 ficount;
> +
> + if (!data)
> + return -EFAULT;
> +
> + if (kstrtouint(data, 0, &ficount))
> + return -EINVAL;
> +
> + ficount &= OCM_FICOUNT_MASK;

Perhaps issue a printk to say that the user value is truncated if the &
is not 0.

> + writel(ficount, priv->baseaddr + OCM_FIC_OFST);
> +
> + return count;
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_cebitpos_show - Shows CE bit position
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + *
> + * Shows the Correctable error bit position,
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_cebitpos_show(struct edac_device_ctl_info
> + *dci, char *data)

Align arguments on the opening brace.

> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + if (priv->ce_bitpos <= UE_MAX_BITPOS_LOWER)
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",

So this is not really intuitive: how does "Fault Injection Data Reg"
mean the CE bit position?

> + ((readl(priv->baseaddr + OCM_FID0_OFST))));
> +
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",
> + ((readl(priv->baseaddr + OCM_FID1_OFST))));

What's in FID1 then?

> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_cebitpos_store - Set CE bit position
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + * @count: read the size bytes from buffer
> + *
> + * Set any one bit to inject CE error
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_cebitpos_store(struct edac_device_ctl_info *dci,
> + const char *data, size_t count)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + if (!data)
> + return -EFAULT;
> +
> + if (kstrtou8(data, 0, &priv->ce_bitpos))
> + return -EINVAL;
> +
> + if (priv->ce_bitpos <= UE_MAX_BITPOS_LOWER) {
> + writel(1 << priv->ce_bitpos, priv->baseaddr + OCM_FID0_OFST);

BIT(priv->ce_bitpos)

and so on.

> + writel(0, priv->baseaddr + OCM_FID1_OFST);
> + } else if (priv->ce_bitpos <= UE_MAX_BITPOS_UPPER) {
> + writel(1 << (priv->ce_bitpos - UE_MIN_BITPOS_UPPER),
> + priv->baseaddr + OCM_FID1_OFST);
> + writel(0, priv->baseaddr + OCM_FID0_OFST);
> + } else {
> + edac_printk(KERN_ERR, EDAC_DEVICE,
> + "Bit number > 64 is not valid\n");

>=

and you can do that checking above, after the kstrtou8() where you don't
return count but an error code.

> + }
> +
> + return count;
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_uebitpos0_show - Shows UE bit postion0
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + *
> + * Shows the one of bit position for UE error
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_uebitpos0_show(struct edac_device_ctl_info *dci,
> + char *data)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + if (priv->ue_bitpos0 <= UE_MAX_BITPOS_LOWER)
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",
> + ((readl(priv->baseaddr + OCM_FID0_OFST))));
> +
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",
> + ((readl(priv->baseaddr + OCM_FID1_OFST))));
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_uebitpos0_store - set UE bit position0
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + * @count: read the size bytes from buffer
> + *
> + * Set the first bit position for UE Error generation,we need to configure
> + * any two bit positions to inject UE Error
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_uebitpos0_store(struct edac_device_ctl_info *dci,
> + const char *data, size_t count)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + if (!data)
> + return -EFAULT;
> +
> + if (kstrtou8(data, 0, &priv->ue_bitpos0))
> + return -EINVAL;
> +
> + if (priv->ue_bitpos0 <= UE_MAX_BITPOS_LOWER)
> + writel(1 << priv->ue_bitpos0, priv->baseaddr + OCM_FID0_OFST);
> + else if (priv->ue_bitpos0 <= UE_MAX_BITPOS_UPPER)
> + writel(1 << (priv->ue_bitpos0 - UE_MIN_BITPOS_UPPER),
> + priv->baseaddr + OCM_FID1_OFST);
> + else
> + edac_printk(KERN_ERR, EDAC_DEVICE,
> + "Bit position > 64 is not valid\n");
> + edac_printk(KERN_INFO, EDAC_DEVICE,
> + "Set another bit position for UE\n");
> +
> + return count;
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_uebitpos1_show - Shows UE bit postion1
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + *
> + * Shows the second bit position configured for UE error
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_uebitpos1_show(struct edac_device_ctl_info *dci,
> + char *data)
> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> +
> + if (priv->ue_bitpos1 <= UE_MAX_BITPOS_LOWER)
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",
> + ((readl(priv->baseaddr + OCM_FID0_OFST))));
> +
> + return sprintf(data, "Fault Injection Data Reg: [0x%x]\n",
> + ((readl(priv->baseaddr + OCM_FID1_OFST))));
> +}
> +
> +/**
> + * zynqmp_ocm_edac_inject_uebitpos1_store - Set UE second bit position
> + * @dci: Pointer to the edac device struct
> + * @data: Pointer to user data
> + * @count: read the size bytes from buffer
> + *
> + * Set the second bit position for UE Error generation,we need to configure
> + * any two bit positions to inject UE Error
> + * Return: Number of bytes copied on success else error code.
> + */
> +static ssize_t zynqmp_ocm_edac_inject_uebitpos1_store(struct edac_device_ctl_info *dci,
> + const char *data, size_t count)

This is clumsy: you wanna have this

echo <uebitpos0>,<uebitpos1> > /sys/kernel/debug/...

and then a *single* function parses those, picks them apart and programs
the hardware.

Not two pretty much independent functions.

> +{
> + struct zynqmp_ocm_edac_priv *priv = dci->pvt_info;
> + u32 mask;
> +
> + if (!data)
> + return -EFAULT;
> +
> + if (kstrtou8(data, 0, &priv->ue_bitpos1))
> + return -EINVAL;
> +
> + if (priv->ue_bitpos0 == priv->ue_bitpos1) {
> + edac_printk(KERN_ERR, EDAC_DEVICE,
> + "Bit positions should not be equal\n");
> + return -EINVAL;
> + }
> +
> + /*
> + * If both bit positions are referring to 32 bit data, then configure
> + * only FID0 register or if it is 64 bit data, then configure only
> + * FID1 register.
> + */
> + if (priv->ue_bitpos0 <= UE_MAX_BITPOS_LOWER &&
> + priv->ue_bitpos1 <= UE_MAX_BITPOS_LOWER) {
> + mask = (1 << priv->ue_bitpos0);
> + mask |= (1 << priv->ue_bitpos1);
> + writel(mask, priv->baseaddr + OCM_FID0_OFST);
> + writel(0, priv->baseaddr + OCM_FID1_OFST);
> + } else if ((priv->ue_bitpos0 >= UE_MIN_BITPOS_UPPER &&
> + priv->ue_bitpos0 <= UE_MAX_BITPOS_UPPER) &&
> + (priv->ue_bitpos1 >= UE_MIN_BITPOS_UPPER &&
> + priv->ue_bitpos1 <= UE_MAX_BITPOS_UPPER)) {
> + mask = (1 << (priv->ue_bitpos0 - UE_MIN_BITPOS_UPPER));
> + mask |= (1 << (priv->ue_bitpos1 - UE_MIN_BITPOS_UPPER));
> + writel(mask, priv->baseaddr + OCM_FID1_OFST);
> + writel(0, priv->baseaddr + OCM_FID0_OFST);
> + }
> +
> + /*
> + * If one bit position is referring a bit in 32 bit data and other in
> + * 64 bit data, just configure FID0/FID1 based on uebitpos1.
> + */
> + if (priv->ue_bitpos0 <= UE_MAX_BITPOS_LOWER &&
> + (priv->ue_bitpos1 >= UE_MIN_BITPOS_UPPER &&
> + priv->ue_bitpos1 <= UE_MAX_BITPOS_UPPER)) {
> + writel(1 << (priv->ue_bitpos1 - UE_MIN_BITPOS_UPPER),
> + priv->baseaddr + OCM_FID1_OFST);
> + } else if ((priv->ue_bitpos0 >= UE_MIN_BITPOS_UPPER &&
> + priv->ue_bitpos0 <= UE_MAX_BITPOS_UPPER) &&
> + (priv->ue_bitpos1 <= UE_MAX_BITPOS_LOWER)) {
> + writel(1 << priv->ue_bitpos1,
> + priv->baseaddr + OCM_FID0_OFST);
> + } else {
> + edac_printk(KERN_ERR, EDAC_DEVICE,
> + "Bit position > 64 is not valid, Valid bits:[63:0]\n");
> + }
> +
> + edac_printk(KERN_INFO, EDAC_DEVICE,
> + "UE at Bit Position0: %d Bit Position1: %d\n",
> + priv->ue_bitpos0, priv->ue_bitpos1);
> +
> + return count;
> +}
> +
> +static struct edac_dev_sysfs_attribute zynqmp_ocm_edac_sysfs_attributes[] = {

debugfs ofc - not sysfs.

> + {
> + .attr = {
> + .name = "inject_cebitpos",
> + .mode = (0644)
> + },
> + .show = zynqmp_ocm_edac_inject_cebitpos_show,
> + .store = zynqmp_ocm_edac_inject_cebitpos_store},
> + {
> + .attr = {
> + .name = "inject_uebitpos0",
> + .mode = (0644)
> + },
> + .show = zynqmp_ocm_edac_inject_uebitpos0_show,
> + .store = zynqmp_ocm_edac_inject_uebitpos0_store},
> + {
> + .attr = {
> + .name = "inject_uebitpos1",
> + .mode = (0644)
> + },
> + .show = zynqmp_ocm_edac_inject_uebitpos1_show,
> + .store = zynqmp_ocm_edac_inject_uebitpos1_store},
> + {
> + .attr = {
> + .name = "inject_fault_count",
> + .mode = (0644)
> + },
> + .show = zynqmp_ocm_edac_inject_fault_count_show,
> + .store = zynqmp_ocm_edac_inject_fault_count_store},
> + /* End of list */
> + {
> + .attr = {.name = NULL}
> + }
> +};
> +
> +/**
> + * zynqmp_set_ocm_edac_sysfs_attributes - create sysfs attributes
> + * @edac_dev: Pointer to the edac device struct
> + *
> + * Creates sysfs entries for error injection
> + */
> +static void zynqmp_set_ocm_edac_sysfs_attributes(struct edac_device_ctl_info
> + *edac_dev)
> +{
> + edac_dev->sysfs_attributes = zynqmp_ocm_edac_sysfs_attributes;
> +}
> +
> +static int zynqmp_ocm_edac_probe(struct platform_device *pdev)
> +{
> + struct zynqmp_ocm_edac_priv *priv;
> + struct edac_device_ctl_info *dci;
> + void __iomem *baseaddr;
> + struct resource *res;
> + int irq, ret;
> +
> + baseaddr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> + if (IS_ERR(baseaddr))
> + return PTR_ERR(baseaddr);
> +
> + if (!zynqmp_ocm_edac_get_eccstate(baseaddr)) {
> + edac_printk(KERN_INFO, EDAC_DEVICE,
> + "ECC not enabled\n");
> + return -ENXIO;
> + }
> +
> + dci = edac_device_alloc_ctl_info(sizeof(*priv), ZYNQMP_OCM_EDAC_STRING,
> + 1, ZYNQMP_OCM_EDAC_STRING, 1, 0, NULL, 0,
> + edac_device_alloc_index());
> + if (!dci)
> + return -ENOMEM;
> +
> + priv = dci->pvt_info;
> + platform_set_drvdata(pdev, dci);
> + dci->dev = &pdev->dev;
> + priv->baseaddr = baseaddr;
> + dci->mod_name = pdev->dev.driver->name;
> + dci->ctl_name = ZYNQMP_OCM_EDAC_STRING;
> + dci->dev_name = dev_name(&pdev->dev);
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + ret = irq;
> + goto free_dev_ctl;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, irq,
> + zynqmp_ocm_edac_intr_handler,
> + 0, dev_name(&pdev->dev), dci);
> + if (ret) {
> + edac_printk(KERN_ERR, EDAC_DEVICE, "Failed to request Irq\n");
> + goto free_dev_ctl;
> + }
> +
> + writel(OCM_CEUE_MASK, priv->baseaddr + OCM_IEN_OFST);

Now that wants to be a separate function or at least have a comment
above it about what it does.

> +
> + zynqmp_set_ocm_edac_sysfs_attributes(dci);

<-- newline

> + ret = edac_device_add_device(dci);
> + if (ret)
> + goto free_dev_ctl;
> +
> + return 0;
> +
> +free_dev_ctl:
> + edac_device_free_ctl_info(dci);
> +
> + return ret;
> +}

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette