2014-06-04 08:18:17

by Bhushan Bharat

[permalink] [raw]
Subject: RE: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver



> -----Original Message-----
> From: Linuxppc-dev [mailto:linuxppc-dev-
> [email protected]] On Behalf Of Scott Wood
> Sent: Saturday, May 31, 2014 3:58 AM
> To: Greg Kroah-Hartman
> Cc: [email protected]; [email protected]
> Subject: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> reporting driver
>
> The CoreNet Coherency Fabric is part of the memory subsystem on some Freescale
> QorIQ chips. It can report coherency violations (e.g.
> due to misusing memory that is mapped noncoherent) as well as transactions that
> do not hit any local access window, or which hit a local access window with an
> invalid target ID.
>
> Signed-off-by: Scott Wood <[email protected]>
> ---
> Resending to the proper list addresses -- sorry for the duplicate.
>
> arch/powerpc/configs/corenet32_smp_defconfig | 1 +
> arch/powerpc/configs/corenet64_smp_defconfig | 1 +
> drivers/memory/Kconfig | 10 ++
> drivers/memory/Makefile | 1 +
> drivers/memory/fsl-corenet-cf.c | 246 +++++++++++++++++++++++++++
> 5 files changed, 259 insertions(+)
> create mode 100644 drivers/memory/fsl-corenet-cf.c
>
> diff --git a/arch/powerpc/configs/corenet32_smp_defconfig
> b/arch/powerpc/configs/corenet32_smp_defconfig
> index c19ff05..0c99d7e 100644
> --- a/arch/powerpc/configs/corenet32_smp_defconfig
> +++ b/arch/powerpc/configs/corenet32_smp_defconfig
> @@ -179,3 +179,4 @@ CONFIG_CRYPTO_SHA512=y CONFIG_CRYPTO_AES=y #
> CONFIG_CRYPTO_ANSI_CPRNG is not set CONFIG_CRYPTO_DEV_FSL_CAAM=y
> +CONFIG_FSL_CORENET_CF=y
> diff --git a/arch/powerpc/configs/corenet64_smp_defconfig
> b/arch/powerpc/configs/corenet64_smp_defconfig
> index 5c7fa19..8fb616d 100644
> --- a/arch/powerpc/configs/corenet64_smp_defconfig
> +++ b/arch/powerpc/configs/corenet64_smp_defconfig
> @@ -175,3 +175,4 @@ CONFIG_CRYPTO_SHA256=y CONFIG_CRYPTO_SHA512=y #
> CONFIG_CRYPTO_ANSI_CPRNG is not set CONFIG_CRYPTO_DEV_FSL_CAAM=y
> +CONFIG_FSL_CORENET_CF=y
> diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig index
> c59e9c9..fab81a1 100644
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> @@ -61,6 +61,16 @@ config TEGRA30_MC
> analysis, especially for IOMMU/SMMU(System Memory Management
> Unit) module.
>
> +config FSL_CORENET_CF
> + tristate "Freescale CoreNet Error Reporting"
> + depends on FSL_SOC_BOOKE
> + help
> + Say Y for reporting of errors from the Freescale CoreNet
> + Coherency Fabric. Errors reported include accesses to
> + physical addresses that mapped by no local access window
> + (LAW) or an invalid LAW, as well as bad cache state that
> + represents a coherency violation.
> +
> config FSL_IFC
> bool
> depends on FSL_SOC
> diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile index
> 71160a2..4055c47 100644
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> @@ -7,6 +7,7 @@ obj-$(CONFIG_OF) += of_memory.o
> endif
> obj-$(CONFIG_TI_AEMIF) += ti-aemif.o
> obj-$(CONFIG_TI_EMIF) += emif.o
> +obj-$(CONFIG_FSL_CORENET_CF) += fsl-corenet-cf.o
> obj-$(CONFIG_FSL_IFC) += fsl_ifc.o
> obj-$(CONFIG_MVEBU_DEVBUS) += mvebu-devbus.o
> obj-$(CONFIG_TEGRA20_MC) += tegra20-mc.o
> diff --git a/drivers/memory/fsl-corenet-cf.c b/drivers/memory/fsl-corenet-cf.c
> new file mode 100644 index 0000000..a57a614
> --- /dev/null
> +++ b/drivers/memory/fsl-corenet-cf.c
> @@ -0,0 +1,246 @@
> +/*
> + * CoreNet Coherency Fabric error reporting
> + *
> + * Copyright 2014 Freescale Semiconductor Inc.
> + *
> + * This program is free software; you can redistribute it and/or
> +modify it
> + * under the terms of the GNU General Public License as published by
> +the
> + * Free Software Foundation; either version 2 of the License, or (at
> +your
> + * option) any later version.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>
> +#include <linux/platform_device.h>
> +
> +enum ccf_version {
> + CCF1,
> + CCF2,
> +};
> +
> +struct ccf_info {
> + enum ccf_version version;
> + int err_reg_offs;
> +};
> +
> +static const struct ccf_info ccf1_info = {
> + .version = CCF1,
> + .err_reg_offs = 0xa00,
> +};
> +
> +static const struct ccf_info ccf2_info = {
> + .version = CCF2,
> + .err_reg_offs = 0xe40,
> +};
> +
> +static const struct of_device_id ccf_matches[] = {
> + {
> + .compatible = "fsl,corenet1-cf",
> + .data = &ccf1_info,
> + },
> + {
> + .compatible = "fsl,corenet2-cf",
> + .data = &ccf2_info,
> + },
> + {}
> +};
> +
> +struct ccf_err_regs {
> + u32 errdet; /* 0x00 Error Detect Register */
> + /* 0x04 Error Enable (ccf1)/Disable (ccf2) Register */
> + u32 errdis;
> + /* 0x08 Error Interrupt Enable Register (ccf2 only) */
> + u32 errinten;
> + u32 cecar; /* 0x0c Error Capture Attribute Register */
> + u32 cecadrh; /* 0x10 Error Capture Address High */

s/cecadrh/cecaddrh/g
This way we will be consistent with Reference manual.

> + u32 cecadrl; /* 0x14 Error Capture Address Low */

s/cecadrl/cecaddrl/g

> + u32 cecar2; /* 0x18 Error Capture Attribute Register 2 */
> +};
> +
> +/* LAE/CV also valid for errdis and errinten */
> +#define ERRDET_LAE (1 << 0) /* Local Access Error */
> +#define ERRDET_CV (1 << 1) /* Coherency Violation */
> +#define ERRDET_CTYPE_SHIFT 26 /* Capture Type (ccf2 only) */
> +#define ERRDET_CTYPE_MASK (0x3f << ERRDET_CTYPE_SHIFT)

Should not this be (0x1f << ERRDET_CTYPE_SHIFT)

> +#define ERRDET_CAP (1 << 31) /* Capture Valid (ccf2 only) */
> +
> +#define CECAR_VAL (1 << 0) /* Valid (ccf1 only) */
> +#define CECAR_UVT (1 << 15) /* Unavailable target ID (ccf1) */
> +#define CECAR_SRCID_SHIFT_CCF1 24
> +#define CECAR_SRCID_MASK_CCF1 (0xff << CECAR_SRCID_SHIFT_CCF1)
> +#define CECAR_SRCID_SHIFT_CCF2 18
> +#define CECAR_SRCID_MASK_CCF2 (0xff << CECAR_SRCID_SHIFT_CCF2)
> +
> +#define CECADRH_ADDRH 0xf

On ccf2 this id 0xff.

> +
> +struct ccf_private {
> + const struct ccf_info *info;
> + struct device *dev;
> + void __iomem *regs;
> + struct ccf_err_regs __iomem *err_regs; };
> +
> +static irqreturn_t ccf_irq(int irq, void *dev_id) {
> + struct ccf_private *ccf = dev_id;
> + static DEFINE_RATELIMIT_STATE(ratelimit, DEFAULT_RATELIMIT_INTERVAL,
> + DEFAULT_RATELIMIT_BURST);
> + u32 errdet, cecar, cecar2;
> + u64 addr;
> + u32 src_id;
> + bool uvt = false;
> + bool cap_valid = false;
> +
> + errdet = ioread32be(&ccf->err_regs->errdet);
> + cecar = ioread32be(&ccf->err_regs->cecar);
> + cecar2 = ioread32be(&ccf->err_regs->cecar2);
> + addr = ioread32be(&ccf->err_regs->cecadrl);
> + addr |= ((u64)(ioread32be(&ccf->err_regs->cecadrh) &
> + CECADRH_ADDRH)) << 32;

So this go down to ccf version type switch.

> +
> + if (!__ratelimit(&ratelimit))
> + goto out;
> +
> + switch (ccf->info->version) {
> + case CCF1:
> + if (cecar & CECAR_VAL) {
> + if (cecar & CECAR_UVT)
> + uvt = true;
> +
> + src_id = (cecar & CECAR_SRCID_MASK_CCF1) >>
> + CECAR_SRCID_SHIFT_CCF1;
> + cap_valid = true;
> + }
> +
> + break;
> + case CCF2:
> + if (errdet & ERRDET_CAP) {
> + src_id = (cecar & CECAR_SRCID_MASK_CCF2) >>
> + CECAR_SRCID_SHIFT_CCF2;
> + cap_valid = true;
> + }
> +
> + break;
> + }
> +
> + dev_crit(ccf->dev, "errdet 0x%08x cecar 0x%08x cecar2 0x%08x\n",
> + errdet, cecar, cecar2);
> +
> + if (errdet & ERRDET_LAE) {
> + if (uvt)
> + dev_crit(ccf->dev, "LAW Unavailable Target ID\n");
> + else
> + dev_crit(ccf->dev, "Local Access Window Error\n");
> + }
> +
> + if (errdet & ERRDET_CV)
> + dev_crit(ccf->dev, "Coherency Violation\n");
> +
> + if (cap_valid) {
> + dev_crit(ccf->dev, "address 0x%09llx, src id 0x%x\n",
> + addr, src_id);
> + }
> +
> +out:
> + iowrite32be(errdet, &ccf->err_regs->errdet);
> + return errdet ? IRQ_HANDLED : IRQ_NONE; }
> +
> +static int ccf_probe(struct platform_device *pdev) {
> + struct ccf_private *ccf;
> + struct resource *r;
> + const struct of_device_id *match;
> + int ret, irq;
> +
> + match = of_match_device(ccf_matches, &pdev->dev);
> + if (WARN_ON(!match))
> + return -ENODEV;
> +
> + ccf = devm_kzalloc(&pdev->dev, sizeof(*ccf), GFP_KERNEL);
> + if (!ccf)
> + return -ENOMEM;
> +
> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!r) {
> + dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
> + return -ENXIO;
> + }
> +
> + ccf->regs = devm_ioremap_resource(&pdev->dev, r);
> + if (IS_ERR(ccf->regs)) {
> + dev_err(&pdev->dev, "%s: can't map mem resource\n", __func__);
> + return PTR_ERR(ccf->regs);
> + }
> +
> + ccf->dev = &pdev->dev;
> + ccf->info = match->data;
> + ccf->err_regs = ccf->regs + ccf->info->err_reg_offs;
> +
> + dev_set_drvdata(&pdev->dev, ccf);
> +
> + irq = platform_get_irq(pdev, 0);
> + if (!irq) {
> + dev_err(&pdev->dev, "%s: no irq\n", __func__);
> + return -ENXIO;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, irq, ccf_irq, 0, pdev->name, ccf);
> + if (ret) {
> + dev_err(&pdev->dev, "%s: can't request irq\n", __func__);
> + return ret;
> + }
> +
> + switch (ccf->info->version) {
> + case CCF1:
> + /* On CCF1 this register enables rather than disables. */
> + iowrite32be(ERRDET_LAE | ERRDET_CV, &ccf->err_regs->errdis);
> + break;
> +
> + case CCF2:
> + iowrite32be(0, &ccf->err_regs->errdis);
> + iowrite32be(ERRDET_LAE | ERRDET_CV, &ccf->err_regs->errinten);
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static int ccf_remove(struct platform_device *pdev) {
> + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> +
> + switch (ccf->info->version) {
> + case CCF1:
> + iowrite32be(0, &ccf->err_regs->errdis);
> + break;
> +
> + case CCF2:
> + iowrite32be(0, &ccf->err_regs->errinten);

Do you think it is same to disable detection bits in ccf->err_regs->errdis?

Thanks
-Bharat

> + break;
> + }
> +
> + return 0;
> +}
> +
> +static struct platform_driver ccf_driver = {
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .owner = THIS_MODULE,
> + .of_match_table = ccf_matches,
> + },
> + .probe = ccf_probe,
> + .remove = ccf_remove,
> +};
> +
> +module_platform_driver(ccf_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Freescale Semiconductor"); MODULE_DESCRIPTION("Freescale
> +CoreNet Coherency Fabric error reporting");
> --
> 1.9.1
> _______________________________________________
> Linuxppc-dev mailing list
> [email protected]
> https://lists.ozlabs.org/listinfo/linuxppc-dev
????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?


2014-06-04 16:42:11

by Scott Wood

[permalink] [raw]
Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver

On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > +struct ccf_err_regs {
> > + u32 errdet; /* 0x00 Error Detect Register */
> > + /* 0x04 Error Enable (ccf1)/Disable (ccf2) Register */
> > + u32 errdis;
> > + /* 0x08 Error Interrupt Enable Register (ccf2 only) */
> > + u32 errinten;
> > + u32 cecar; /* 0x0c Error Capture Attribute Register */
> > + u32 cecadrh; /* 0x10 Error Capture Address High */
>
> s/cecadrh/cecaddrh/g
> This way we will be consistent with Reference manual.

It's "cecadrh" in ccf1 and "cecaddrh" in ccf2. I suppose I should use
the latter since "errdet/errdis/errinten" are the ccf2 names.

> > + u32 cecadrl; /* 0x14 Error Capture Address Low */
>
> s/cecadrl/cecaddrl/g
>
> > + u32 cecar2; /* 0x18 Error Capture Attribute Register 2 */
> > +};
> > +
> > +/* LAE/CV also valid for errdis and errinten */
> > +#define ERRDET_LAE (1 << 0) /* Local Access Error */
> > +#define ERRDET_CV (1 << 1) /* Coherency Violation */
> > +#define ERRDET_CTYPE_SHIFT 26 /* Capture Type (ccf2 only) */
> > +#define ERRDET_CTYPE_MASK (0x3f << ERRDET_CTYPE_SHIFT)
>
> Should not this be (0x1f << ERRDET_CTYPE_SHIFT)

Yes, thanks for catching that.

> > +#define ERRDET_CAP (1 << 31) /* Capture Valid (ccf2 only) */
> > +
> > +#define CECAR_VAL (1 << 0) /* Valid (ccf1 only) */
> > +#define CECAR_UVT (1 << 15) /* Unavailable target ID (ccf1) */
> > +#define CECAR_SRCID_SHIFT_CCF1 24
> > +#define CECAR_SRCID_MASK_CCF1 (0xff << CECAR_SRCID_SHIFT_CCF1)
> > +#define CECAR_SRCID_SHIFT_CCF2 18
> > +#define CECAR_SRCID_MASK_CCF2 (0xff << CECAR_SRCID_SHIFT_CCF2)
> > +
> > +#define CECADRH_ADDRH 0xf
>
> On ccf2 this id 0xff.

OK. I think we can get away with using 0xff on both.

> > +static int ccf_remove(struct platform_device *pdev) {
> > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > +
> > + switch (ccf->info->version) {
> > + case CCF1:
> > + iowrite32be(0, &ccf->err_regs->errdis);
> > + break;
> > +
> > + case CCF2:
> > + iowrite32be(0, &ccf->err_regs->errinten);
>
> Do you think it is same to disable detection bits in ccf->err_regs->errdis?

Disabling the interrupt is what we're aiming for here, but ccf1 doesn't
provide a way to do that separate from disabling detection.

-Scott

2014-06-04 17:04:56

by Bhushan Bharat

[permalink] [raw]
Subject: RE: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver



> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Wednesday, June 04, 2014 10:12 PM
> To: Bhushan Bharat-R65777
> Cc: Greg Kroah-Hartman; [email protected]; linux-
> [email protected]
> Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> reporting driver
>
> On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > > +struct ccf_err_regs {
> > > + u32 errdet; /* 0x00 Error Detect Register */
> > > + /* 0x04 Error Enable (ccf1)/Disable (ccf2) Register */
> > > + u32 errdis;
> > > + /* 0x08 Error Interrupt Enable Register (ccf2 only) */
> > > + u32 errinten;
> > > + u32 cecar; /* 0x0c Error Capture Attribute Register */
> > > + u32 cecadrh; /* 0x10 Error Capture Address High */
> >
> > s/cecadrh/cecaddrh/g
> > This way we will be consistent with Reference manual.
>
> It's "cecadrh" in ccf1 and "cecaddrh" in ccf2. I suppose I should use the
> latter since "errdet/errdis/errinten" are the ccf2 names.
>
> > > + u32 cecadrl; /* 0x14 Error Capture Address Low */
> >
> > s/cecadrl/cecaddrl/g
> >
> > > + u32 cecar2; /* 0x18 Error Capture Attribute Register 2 */
> > > +};
> > > +
> > > +/* LAE/CV also valid for errdis and errinten */
> > > +#define ERRDET_LAE (1 << 0) /* Local Access Error */
> > > +#define ERRDET_CV (1 << 1) /* Coherency Violation */
> > > +#define ERRDET_CTYPE_SHIFT 26 /* Capture Type (ccf2 only) */
> > > +#define ERRDET_CTYPE_MASK (0x3f << ERRDET_CTYPE_SHIFT)
> >
> > Should not this be (0x1f << ERRDET_CTYPE_SHIFT)
>
> Yes, thanks for catching that.
>
> > > +#define ERRDET_CAP (1 << 31) /* Capture Valid (ccf2 only) */
> > > +
> > > +#define CECAR_VAL (1 << 0) /* Valid (ccf1 only) */
> > > +#define CECAR_UVT (1 << 15) /* Unavailable target ID (ccf1) */
> > > +#define CECAR_SRCID_SHIFT_CCF1 24
> > > +#define CECAR_SRCID_MASK_CCF1 (0xff << CECAR_SRCID_SHIFT_CCF1)
> > > +#define CECAR_SRCID_SHIFT_CCF2 18
> > > +#define CECAR_SRCID_MASK_CCF2 (0xff << CECAR_SRCID_SHIFT_CCF2)
> > > +
> > > +#define CECADRH_ADDRH 0xf
> >
> > On ccf2 this id 0xff.
>
> OK. I think we can get away with using 0xff on both.
>
> > > +static int ccf_remove(struct platform_device *pdev) {
> > > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > > +
> > > + switch (ccf->info->version) {
> > > + case CCF1:
> > > + iowrite32be(0, &ccf->err_regs->errdis);
> > > + break;
> > > +
> > > + case CCF2:
> > > + iowrite32be(0, &ccf->err_regs->errinten);
> >
> > Do you think it is same to disable detection bits in ccf->err_regs->errdis?
>
> Disabling the interrupt is what we're aiming for here, but ccf1 doesn't provide
> a way to do that separate from disabling detection.

What I wanted to say that do we also need to disable detection (set ERRDET_LAE | ERRDET_CV bits in errdis) apart from clearing errinten on ccf2 ?

Thanks
-Bharat

>
> -Scott
>

????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?

2014-06-04 17:07:46

by Scott Wood

[permalink] [raw]
Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver

On Wed, 2014-06-04 at 12:04 -0500, Bhushan Bharat-R65777 wrote:
>
> > -----Original Message-----
> > From: Wood Scott-B07421
> > Sent: Wednesday, June 04, 2014 10:12 PM
> > To: Bhushan Bharat-R65777
> > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > [email protected]
> > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> > reporting driver
> >
> > On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > > > +static int ccf_remove(struct platform_device *pdev) {
> > > > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > > > +
> > > > + switch (ccf->info->version) {
> > > > + case CCF1:
> > > > + iowrite32be(0, &ccf->err_regs->errdis);
> > > > + break;
> > > > +
> > > > + case CCF2:
> > > > + iowrite32be(0, &ccf->err_regs->errinten);
> > >
> > > Do you think it is same to disable detection bits in ccf->err_regs->errdis?
> >
> > Disabling the interrupt is what we're aiming for here, but ccf1 doesn't provide
> > a way to do that separate from disabling detection.
>
> What I wanted to say that do we also need to disable detection (set
> ERRDET_LAE | ERRDET_CV bits in errdis) apart from clearing errinten on
> ccf2 ?

I don't think we "need" to. You could argue that we should for
consistency, though I think there's value in errors continuing to be
detected even without the driver (e.g. can dump the registers in a
debugger).

-Scott

2014-06-30 04:59:03

by Bhushan Bharat

[permalink] [raw]
Subject: RE: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver



> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Wednesday, June 04, 2014 10:38 PM
> To: Bhushan Bharat-R65777
> Cc: Greg Kroah-Hartman; [email protected]; linux-
> [email protected]
> Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> reporting driver
>
> On Wed, 2014-06-04 at 12:04 -0500, Bhushan Bharat-R65777 wrote:
> >
> > > -----Original Message-----
> > > From: Wood Scott-B07421
> > > Sent: Wednesday, June 04, 2014 10:12 PM
> > > To: Bhushan Bharat-R65777
> > > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > > [email protected]
> > > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency
> > > Fabric error reporting driver
> > >
> > > On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > > > > +static int ccf_remove(struct platform_device *pdev) {
> > > > > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > > > > +
> > > > > + switch (ccf->info->version) {
> > > > > + case CCF1:
> > > > > + iowrite32be(0, &ccf->err_regs->errdis);
> > > > > + break;
> > > > > +
> > > > > + case CCF2:
> > > > > + iowrite32be(0, &ccf->err_regs->errinten);
> > > >
> > > > Do you think it is same to disable detection bits in ccf->err_regs-
> >errdis?
> > >
> > > Disabling the interrupt is what we're aiming for here, but ccf1
> > > doesn't provide a way to do that separate from disabling detection.
> >
> > What I wanted to say that do we also need to disable detection (set
> > ERRDET_LAE | ERRDET_CV bits in errdis) apart from clearing errinten on
> > ccf2 ?
>
> I don't think we "need" to. You could argue that we should for consistency,
> though I think there's value in errors continuing to be detected even without
> the driver (e.g. can dump the registers in a debugger).

Yes this comment was for consistency. Also IIUC, the state which is left when the driver is removed is not default reset behavior.
If we want errors to be detected then should not we have a sysfs interface?

Thanks
-Bharat

>
> -Scott
>

????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?

2014-06-30 20:59:55

by Scott Wood

[permalink] [raw]
Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver

On Sun, 2014-06-29 at 23:58 -0500, Bhushan Bharat-R65777 wrote:
>
> > -----Original Message-----
> > From: Wood Scott-B07421
> > Sent: Wednesday, June 04, 2014 10:38 PM
> > To: Bhushan Bharat-R65777
> > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > [email protected]
> > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> > reporting driver
> >
> > On Wed, 2014-06-04 at 12:04 -0500, Bhushan Bharat-R65777 wrote:
> > >
> > > > -----Original Message-----
> > > > From: Wood Scott-B07421
> > > > Sent: Wednesday, June 04, 2014 10:12 PM
> > > > To: Bhushan Bharat-R65777
> > > > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > > > [email protected]
> > > > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency
> > > > Fabric error reporting driver
> > > >
> > > > On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > > > > > +static int ccf_remove(struct platform_device *pdev) {
> > > > > > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > > > > > +
> > > > > > + switch (ccf->info->version) {
> > > > > > + case CCF1:
> > > > > > + iowrite32be(0, &ccf->err_regs->errdis);
> > > > > > + break;
> > > > > > +
> > > > > > + case CCF2:
> > > > > > + iowrite32be(0, &ccf->err_regs->errinten);
> > > > >
> > > > > Do you think it is same to disable detection bits in ccf->err_regs-
> > >errdis?
> > > >
> > > > Disabling the interrupt is what we're aiming for here, but ccf1
> > > > doesn't provide a way to do that separate from disabling detection.
> > >
> > > What I wanted to say that do we also need to disable detection (set
> > > ERRDET_LAE | ERRDET_CV bits in errdis) apart from clearing errinten on
> > > ccf2 ?
> >
> > I don't think we "need" to. You could argue that we should for consistency,
> > though I think there's value in errors continuing to be detected even without
> > the driver (e.g. can dump the registers in a debugger).
>
> Yes this comment was for consistency. Also IIUC, the state which is left when the driver is removed is not default reset behavior.

How many drivers leave the hardware in pristine reset state when
exiting? And you could argue that having detection off by default is
poor hardware design (enabling interrupts is another matter of course).

> If we want errors to be detected then should not we have a sysfs interface?

That may be useful but it's beyond the scope of what I'm doing with this
patch. We currently don't log machine checks anywhere but via printk
either.

BTW, I thought I had sent v2 of this, but I don't see it anywhere...
I'll respin soon.

-Scott

2014-07-01 04:16:54

by Bhushan Bharat

[permalink] [raw]
Subject: RE: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error reporting driver



> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Tuesday, July 01, 2014 2:30 AM
> To: Bhushan Bharat-R65777
> Cc: Greg Kroah-Hartman; [email protected]; linux-
> [email protected]
> Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency Fabric error
> reporting driver
>
> On Sun, 2014-06-29 at 23:58 -0500, Bhushan Bharat-R65777 wrote:
> >
> > > -----Original Message-----
> > > From: Wood Scott-B07421
> > > Sent: Wednesday, June 04, 2014 10:38 PM
> > > To: Bhushan Bharat-R65777
> > > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > > [email protected]
> > > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency
> > > Fabric error reporting driver
> > >
> > > On Wed, 2014-06-04 at 12:04 -0500, Bhushan Bharat-R65777 wrote:
> > > >
> > > > > -----Original Message-----
> > > > > From: Wood Scott-B07421
> > > > > Sent: Wednesday, June 04, 2014 10:12 PM
> > > > > To: Bhushan Bharat-R65777
> > > > > Cc: Greg Kroah-Hartman; [email protected]; linux-
> > > > > [email protected]
> > > > > Subject: Re: [RESEND PATCH] memory: Freescale CoreNet Coherency
> > > > > Fabric error reporting driver
> > > > >
> > > > > On Wed, 2014-06-04 at 03:17 -0500, Bhushan Bharat-R65777 wrote:
> > > > > > > +static int ccf_remove(struct platform_device *pdev) {
> > > > > > > + struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
> > > > > > > +
> > > > > > > + switch (ccf->info->version) {
> > > > > > > + case CCF1:
> > > > > > > + iowrite32be(0, &ccf->err_regs->errdis);
> > > > > > > + break;
> > > > > > > +
> > > > > > > + case CCF2:
> > > > > > > + iowrite32be(0, &ccf->err_regs->errinten);
> > > > > >
> > > > > > Do you think it is same to disable detection bits in
> > > > > > ccf->err_regs-
> > > >errdis?
> > > > >
> > > > > Disabling the interrupt is what we're aiming for here, but ccf1
> > > > > doesn't provide a way to do that separate from disabling detection.
> > > >
> > > > What I wanted to say that do we also need to disable detection
> > > > (set ERRDET_LAE | ERRDET_CV bits in errdis) apart from clearing
> > > > errinten on
> > > > ccf2 ?
> > >
> > > I don't think we "need" to. You could argue that we should for
> > > consistency, though I think there's value in errors continuing to be
> > > detected even without the driver (e.g. can dump the registers in a
> debugger).
> >
> > Yes this comment was for consistency. Also IIUC, the state which is left when
> the driver is removed is not default reset behavior.
>
> How many drivers leave the hardware in pristine reset state when exiting?

I do not know :)

> And
> you could argue that having detection off by default is poor hardware design
> (enabling interrupts is another matter of course).

Ok, then can you please add a comment in _remove() function describing why detection is still enabled.

Thanks
-Bharat

>
> > If we want errors to be detected then should not we have a sysfs interface?
>
> That may be useful but it's beyond the scope of what I'm doing with this patch.
> We currently don't log machine checks anywhere but via printk either.
>
> BTW, I thought I had sent v2 of this, but I don't see it anywhere...
> I'll respin soon.
>
> -Scott
>

????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?