2020-07-28 09:54:10

by Shenhar, Talel

[permalink] [raw]
Subject: [PATCH v9 2/2] EDAC: al-mc-edac: Introduce Amazon's Annapurna Labs Memory Controller EDAC

The Amazon's Annapurna Labs Memory Controller EDAC supports ECC capability
for error detection and correction (Single bit error correction, Double
detection). This driver introduces EDAC driver for that capability.

Signed-off-by: Talel Shenhar <[email protected]>
Reviewed-by: James Morse <[email protected]>
---
MAINTAINERS | 7 +
drivers/edac/Kconfig | 7 +
drivers/edac/Makefile | 1 +
drivers/edac/al_mc_edac.c | 354 ++++++++++++++++++++++++++++++++++++++
4 files changed, 369 insertions(+)
create mode 100644 drivers/edac/al_mc_edac.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 68f21d46614c..0e6532c37bef 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -802,6 +802,13 @@ S: Maintained
F: Documentation/devicetree/bindings/interrupt-controller/amazon,al-fic.txt
F: drivers/irqchip/irq-al-fic.c

+AMAZON ANNAPURNA LABS MEMORY CONTROLLER EDAC
+M: Talel Shenhar <[email protected]>
+M: Talel Shenhar <[email protected]>
+S: Maintained
+F: Documentation/devicetree/bindings/edac/amazon,al-mc-edac.yaml
+F: drivers/edac/al_mc_edac.c
+
AMAZON ANNAPURNA LABS THERMAL MMIO DRIVER
M: Talel Shenhar <[email protected]>
S: Maintained
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 7b6ec3014ba2..e3002718b1f5 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -100,6 +100,13 @@ config EDAC_AMD64_ERROR_INJECTION
In addition, there are two control files, inject_read and inject_write,
which trigger the DRAM ECC Read and Write respectively.

+config EDAC_AL_MC
+ tristate "Amazon's Annapurna Lab EDAC Memory Controller"
+ depends on (ARCH_ALPINE || COMPILE_TEST)
+ help
+ Support for error detection and correction for Amazon's Annapurna
+ Labs Alpine chips which allows 1 bit correction and 2 bits detection.
+
config EDAC_AMD76X
tristate "AMD 76x (760, 762, 768)"
depends on PCI && X86_32
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 269e15118cea..3a849168780d 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_EDAC_GHES) += ghes_edac.o
edac_mce_amd-y := mce_amd.o
obj-$(CONFIG_EDAC_DECODE_MCE) += edac_mce_amd.o

+obj-$(CONFIG_EDAC_AL_MC) += al_mc_edac.o
obj-$(CONFIG_EDAC_AMD76X) += amd76x_edac.o
obj-$(CONFIG_EDAC_CPC925) += cpc925_edac.o
obj-$(CONFIG_EDAC_I5000) += i5000_edac.o
diff --git a/drivers/edac/al_mc_edac.c b/drivers/edac/al_mc_edac.c
new file mode 100644
index 000000000000..b0ee48775c62
--- /dev/null
+++ b/drivers/edac/al_mc_edac.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/edac.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include "edac_module.h"
+
+/* Registers Offset */
+#define AL_MC_ECC_CFG 0x70
+#define AL_MC_ECC_CLEAR 0x7c
+#define AL_MC_ECC_ERR_COUNT 0x80
+#define AL_MC_ECC_CE_ADDR0 0x84
+#define AL_MC_ECC_CE_ADDR1 0x88
+#define AL_MC_ECC_UE_ADDR0 0xa4
+#define AL_MC_ECC_UE_ADDR1 0xa8
+#define AL_MC_ECC_CE_SYND0 0x8c
+#define AL_MC_ECC_CE_SYND1 0x90
+#define AL_MC_ECC_CE_SYND2 0x94
+#define AL_MC_ECC_UE_SYND0 0xac
+#define AL_MC_ECC_UE_SYND1 0xb0
+#define AL_MC_ECC_UE_SYND2 0xb4
+
+/* Registers Fields */
+#define AL_MC_ECC_CFG_SCRUB_DISABLED BIT(4)
+
+#define AL_MC_ECC_CLEAR_UE_COUNT BIT(3)
+#define AL_MC_ECC_CLEAR_CE_COUNT BIT(2)
+#define AL_MC_ECC_CLEAR_UE_ERR BIT(1)
+#define AL_MC_ECC_CLEAR_CE_ERR BIT(0)
+
+#define AL_MC_ECC_ERR_COUNT_UE GENMASK(31, 16)
+#define AL_MC_ECC_ERR_COUNT_CE GENMASK(15, 0)
+
+#define AL_MC_ECC_CE_ADDR0_RANK GENMASK(25, 24)
+#define AL_MC_ECC_CE_ADDR0_ROW GENMASK(17, 0)
+
+#define AL_MC_ECC_CE_ADDR1_BG GENMASK(25, 24)
+#define AL_MC_ECC_CE_ADDR1_BANK GENMASK(18, 16)
+#define AL_MC_ECC_CE_ADDR1_COLUMN GENMASK(11, 0)
+
+#define AL_MC_ECC_UE_ADDR0_RANK GENMASK(25, 24)
+#define AL_MC_ECC_UE_ADDR0_ROW GENMASK(17, 0)
+
+#define AL_MC_ECC_UE_ADDR1_BG GENMASK(25, 24)
+#define AL_MC_ECC_UE_ADDR1_BANK GENMASK(18, 16)
+#define AL_MC_ECC_UE_ADDR1_COLUMN GENMASK(11, 0)
+
+#define DRV_NAME "al_mc_edac"
+#define AL_MC_EDAC_MSG_MAX 256
+
+struct al_mc_edac {
+ void __iomem *mmio_base;
+ spinlock_t lock;
+ int irq_ce;
+ int irq_ue;
+};
+
+static void prepare_msg(char *message, size_t buffer_size,
+ enum hw_event_mc_err_type type,
+ u8 rank, u32 row, u8 bg, u8 bank, u16 column,
+ u32 syn0, u32 syn1, u32 syn2)
+{
+ snprintf(message, buffer_size,
+ "%s rank=0x%x row=0x%x bg=0x%x bank=0x%x col=0x%x syn0: 0x%x syn1: 0x%x syn2: 0x%x",
+ type == HW_EVENT_ERR_UNCORRECTED ? "UE" : "CE",
+ rank, row, bg, bank, column, syn0, syn1, syn2);
+}
+
+static int handle_ce(struct mem_ctl_info *mci)
+{
+ u32 eccerrcnt, ecccaddr0, ecccaddr1, ecccsyn0, ecccsyn1, ecccsyn2, row;
+ struct al_mc_edac *al_mc = mci->pvt_info;
+ char msg[AL_MC_EDAC_MSG_MAX];
+ u16 ce_count, column;
+ unsigned long flags;
+ u8 rank, bg, bank;
+
+ eccerrcnt = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_ERR_COUNT);
+ ce_count = FIELD_GET(AL_MC_ECC_ERR_COUNT_CE, eccerrcnt);
+ if (!ce_count)
+ return 0;
+
+ ecccaddr0 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_CE_ADDR0);
+ ecccaddr1 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_CE_ADDR1);
+ ecccsyn0 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_CE_SYND0);
+ ecccsyn1 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_CE_SYND1);
+ ecccsyn2 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_CE_SYND2);
+
+ writel_relaxed(AL_MC_ECC_CLEAR_CE_COUNT | AL_MC_ECC_CLEAR_CE_ERR,
+ al_mc->mmio_base + AL_MC_ECC_CLEAR);
+
+ dev_dbg(mci->pdev, "eccuaddr0=0x%08x eccuaddr1=0x%08x\n",
+ ecccaddr0, ecccaddr1);
+
+ rank = FIELD_GET(AL_MC_ECC_CE_ADDR0_RANK, ecccaddr0);
+ row = FIELD_GET(AL_MC_ECC_CE_ADDR0_ROW, ecccaddr0);
+
+ bg = FIELD_GET(AL_MC_ECC_CE_ADDR1_BG, ecccaddr1);
+ bank = FIELD_GET(AL_MC_ECC_CE_ADDR1_BANK, ecccaddr1);
+ column = FIELD_GET(AL_MC_ECC_CE_ADDR1_COLUMN, ecccaddr1);
+
+ prepare_msg(msg, sizeof(msg), HW_EVENT_ERR_CORRECTED,
+ rank, row, bg, bank, column,
+ ecccsyn0, ecccsyn1, ecccsyn2);
+
+ spin_lock_irqsave(&al_mc->lock, flags);
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
+ ce_count, 0, 0, 0, 0, 0, -1, mci->ctl_name, msg);
+ spin_unlock_irqrestore(&al_mc->lock, flags);
+
+ return ce_count;
+}
+
+static int handle_ue(struct mem_ctl_info *mci)
+{
+ u32 eccerrcnt, eccuaddr0, eccuaddr1, eccusyn0, eccusyn1, eccusyn2, row;
+ struct al_mc_edac *al_mc = mci->pvt_info;
+ char msg[AL_MC_EDAC_MSG_MAX];
+ u16 ue_count, column;
+ unsigned long flags;
+ u8 rank, bg, bank;
+
+ eccerrcnt = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_ERR_COUNT);
+ ue_count = FIELD_GET(AL_MC_ECC_ERR_COUNT_UE, eccerrcnt);
+ if (!ue_count)
+ return 0;
+
+ eccuaddr0 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_UE_ADDR0);
+ eccuaddr1 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_UE_ADDR1);
+ eccusyn0 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_UE_SYND0);
+ eccusyn1 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_UE_SYND1);
+ eccusyn2 = readl_relaxed(al_mc->mmio_base + AL_MC_ECC_UE_SYND2);
+
+ writel_relaxed(AL_MC_ECC_CLEAR_UE_COUNT | AL_MC_ECC_CLEAR_UE_ERR,
+ al_mc->mmio_base + AL_MC_ECC_CLEAR);
+
+ dev_dbg(mci->pdev, "eccuaddr0=0x%08x eccuaddr1=0x%08x\n",
+ eccuaddr0, eccuaddr1);
+
+ rank = FIELD_GET(AL_MC_ECC_UE_ADDR0_RANK, eccuaddr0);
+ row = FIELD_GET(AL_MC_ECC_UE_ADDR0_ROW, eccuaddr0);
+
+ bg = FIELD_GET(AL_MC_ECC_UE_ADDR1_BG, eccuaddr1);
+ bank = FIELD_GET(AL_MC_ECC_UE_ADDR1_BANK, eccuaddr1);
+ column = FIELD_GET(AL_MC_ECC_UE_ADDR1_COLUMN, eccuaddr1);
+
+ prepare_msg(msg, sizeof(msg), HW_EVENT_ERR_UNCORRECTED,
+ rank, row, bg, bank, column,
+ eccusyn0, eccusyn1, eccusyn2);
+
+ spin_lock_irqsave(&al_mc->lock, flags);
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
+ ue_count, 0, 0, 0, 0, 0, -1, mci->ctl_name, msg);
+ spin_unlock_irqrestore(&al_mc->lock, flags);
+
+ return ue_count;
+}
+
+static void al_mc_edac_check(struct mem_ctl_info *mci)
+{
+ struct al_mc_edac *al_mc = mci->pvt_info;
+
+ if (al_mc->irq_ue <= 0)
+ handle_ue(mci);
+
+ if (al_mc->irq_ce <= 0)
+ handle_ce(mci);
+}
+
+static irqreturn_t al_mc_edac_irq_handler_ue(int irq, void *info)
+{
+ struct platform_device *pdev = info;
+ struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+
+ if (handle_ue(mci))
+ return IRQ_HANDLED;
+ return IRQ_NONE;
+}
+
+static irqreturn_t al_mc_edac_irq_handler_ce(int irq, void *info)
+{
+ struct platform_device *pdev = info;
+ struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+
+ if (handle_ce(mci))
+ return IRQ_HANDLED;
+ return IRQ_NONE;
+}
+
+static enum scrub_type al_mc_edac_get_scrub_mode(void __iomem *mmio_base)
+{
+ u32 ecccfg0;
+
+ ecccfg0 = readl(mmio_base + AL_MC_ECC_CFG);
+
+ if (FIELD_GET(AL_MC_ECC_CFG_SCRUB_DISABLED, ecccfg0))
+ return SCRUB_NONE;
+ else
+ return SCRUB_HW_SRC;
+}
+
+static void devm_al_mc_edac_free(void *data)
+{
+ edac_mc_free(data);
+}
+
+static void devm_al_mc_edac_del(void *data)
+{
+ edac_mc_del_mc(data);
+}
+
+static int al_mc_edac_probe(struct platform_device *pdev)
+{
+ struct edac_mc_layer layers[1];
+ struct mem_ctl_info *mci;
+ struct al_mc_edac *al_mc;
+ void __iomem *mmio_base;
+ struct dimm_info *dimm;
+ int ret;
+
+ mmio_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mmio_base)) {
+ dev_err(&pdev->dev, "failed to ioremap memory (%ld)\n",
+ PTR_ERR(mmio_base));
+ return PTR_ERR(mmio_base);
+ }
+
+ layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+ layers[0].size = 1;
+ layers[0].is_virt_csrow = false;
+ mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
+ sizeof(struct al_mc_edac));
+ if (!mci)
+ return -ENOMEM;
+
+ ret = devm_add_action(&pdev->dev, devm_al_mc_edac_free, mci);
+ if (ret) {
+ edac_mc_free(mci);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, mci);
+ al_mc = mci->pvt_info;
+
+ al_mc->mmio_base = mmio_base;
+
+ al_mc->irq_ue = of_irq_get_byname(pdev->dev.of_node, "ue");
+ if (al_mc->irq_ue <= 0)
+ dev_dbg(&pdev->dev,
+ "no IRQ defined for UE - falling back to polling\n");
+
+ al_mc->irq_ce = of_irq_get_byname(pdev->dev.of_node, "ce");
+ if (al_mc->irq_ce <= 0)
+ dev_dbg(&pdev->dev,
+ "no IRQ defined for CE - falling back to polling\n");
+
+ /*
+ * In case both interrupts (ue/ce) are to be found, use interrupt mode.
+ * In case none of the interrupt are foud, use polling mode.
+ * In case only one interrupt is found, use interrupt mode for it but
+ * keep polling mode enable for the other.
+ */
+ if (al_mc->irq_ue <= 0 || al_mc->irq_ce <= 0) {
+ edac_op_state = EDAC_OPSTATE_POLL;
+ mci->edac_check = al_mc_edac_check;
+ } else {
+ edac_op_state = EDAC_OPSTATE_INT;
+ }
+
+ spin_lock_init(&al_mc->lock);
+
+ mci->mtype_cap = MEM_FLAG_DDR3 | MEM_FLAG_DDR4;
+ mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
+ mci->edac_cap = EDAC_FLAG_SECDED;
+ mci->mod_name = DRV_NAME;
+ mci->ctl_name = "al_mc";
+ mci->pdev = &pdev->dev;
+ mci->scrub_mode = al_mc_edac_get_scrub_mode(mmio_base);
+
+ dimm = *mci->dimms;
+ dimm->grain = 1;
+
+ ret = edac_mc_add_mc(mci);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "fail to add memory controller device (%d)\n",
+ ret);
+ return ret;
+ }
+
+ ret = devm_add_action(&pdev->dev, devm_al_mc_edac_del, &pdev->dev);
+ if (ret) {
+ edac_mc_del_mc(&pdev->dev);
+ return ret;
+ }
+
+ if (al_mc->irq_ue > 0) {
+ ret = devm_request_irq(&pdev->dev,
+ al_mc->irq_ue,
+ al_mc_edac_irq_handler_ue,
+ IRQF_SHARED,
+ pdev->name,
+ pdev);
+ if (ret != 0) {
+ dev_err(&pdev->dev,
+ "failed to request UE IRQ %d (%d)\n",
+ al_mc->irq_ue, ret);
+ return ret;
+ }
+ }
+
+ if (al_mc->irq_ce > 0) {
+ ret = devm_request_irq(&pdev->dev,
+ al_mc->irq_ce,
+ al_mc_edac_irq_handler_ce,
+ IRQF_SHARED,
+ pdev->name,
+ pdev);
+ if (ret != 0) {
+ dev_err(&pdev->dev,
+ "failed to request CE IRQ %d (%d)\n",
+ al_mc->irq_ce, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct of_device_id al_mc_edac_of_match[] = {
+ { .compatible = "amazon,al-mc-edac", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, al_mc_edac_of_match);
+
+static struct platform_driver al_mc_edac_driver = {
+ .probe = al_mc_edac_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = al_mc_edac_of_match,
+ },
+};
+
+module_platform_driver(al_mc_edac_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Talel Shenhar");
+MODULE_DESCRIPTION("Amazon's Annapurna Lab's Memory Controller EDAC Driver");
--
2.17.1


2020-08-16 02:06:39

by Borislav Petkov

[permalink] [raw]
Subject: Re: [PATCH v9 2/2] EDAC: al-mc-edac: Introduce Amazon's Annapurna Labs Memory Controller EDAC

On Tue, Jul 28, 2020 at 12:51:55PM +0300, Talel Shenhar wrote:
> +static void al_mc_edac_check(struct mem_ctl_info *mci)
> +{
> + struct al_mc_edac *al_mc = mci->pvt_info;
> +
> + if (al_mc->irq_ue <= 0)
> + handle_ue(mci);
> +
> + if (al_mc->irq_ce <= 0)
> + handle_ce(mci);
> +}
> +
> +static irqreturn_t al_mc_edac_irq_handler_ue(int irq, void *info)
> +{
> + struct platform_device *pdev = info;
> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
> +
> + if (handle_ue(mci))
> + return IRQ_HANDLED;
> + return IRQ_NONE;
> +}
> +
> +static irqreturn_t al_mc_edac_irq_handler_ce(int irq, void *info)
> +{
> + struct platform_device *pdev = info;
> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
> +
> + if (handle_ce(mci))
> + return IRQ_HANDLED;
> + return IRQ_NONE;
> +}
> +
> +static enum scrub_type al_mc_edac_get_scrub_mode(void __iomem *mmio_base)
> +{
> + u32 ecccfg0;
> +
> + ecccfg0 = readl(mmio_base + AL_MC_ECC_CFG);
> +
> + if (FIELD_GET(AL_MC_ECC_CFG_SCRUB_DISABLED, ecccfg0))
> + return SCRUB_NONE;
> + else
> + return SCRUB_HW_SRC;
> +}
> +
> +static void devm_al_mc_edac_free(void *data)
> +{
> + edac_mc_free(data);
> +}
> +
> +static void devm_al_mc_edac_del(void *data)
> +{
> + edac_mc_del_mc(data);
> +}

From a previous review:

I said:

> Drop the "al_mc_edac_" prefix from most of the static functions. You can
> leave it in the probe function or the IRQ handler so that it is visible
> in stack traces but all those small functions don't need that prefix.

You replied with:

> Shall be part of v7.

and yet it ain't part of any v<num>.

Why?

--
Regards/Gruss,
Boris.

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

2020-08-16 12:17:09

by Shenhar, Talel

[permalink] [raw]
Subject: Re: [PATCH v9 2/2] EDAC: al-mc-edac: Introduce Amazon's Annapurna Labs Memory Controller EDAC


On 8/16/2020 2:22 PM, Borislav Petkov wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
> On Sun, Aug 16, 2020 at 12:17:31PM +0300, Shenhar, Talel wrote:
>> Let me know what you think.
> Well, devm_al_mc_edac_free() devm_al_mc_edac_del() look like useless
> wrappers to me and can be removed and you can use edac_mc_del_mc() and
> edac_mc_free() directly. But then you need to cast them in an ugly way
> so that it builds:
>
> ret = devm_add_action(&pdev->dev, (void (*)(void *data))edac_mc_free, mci);
>
> I guess we can leave them as is and then lift them into the EDAC core if
> someone else wants to do the same devm_* thing.
>
> al_mc_edac_get_scrub_mode() doesn't need a prefix because it is used
> only once and the compiler is simply inlining it so you can forget the
> stack trace visibility:
>
> $ readelf -s drivers/edac/al_mc_edac.ko | grep scrub
> $
>
> The others are fine, I guess, since they're function pointers and cannot be
> inlined as such so you want them prefixed:
>
> $ readelf -s drivers/edac/al_mc_edac.ko | grep al_mc_edac
> 23: 00000000 0 FILE LOCAL DEFAULT ABS al_mc_edac.c
> 25: 00000000 4 FUNC LOCAL DEFAULT 1 devm_al_mc_edac_free
> 27: 00000004 4 FUNC LOCAL DEFAULT 1 devm_al_mc_edac_del
> 31: 00000124 24 FUNC LOCAL DEFAULT 1 al_mc_edac_irq_handler_ce
> 35: 00000260 24 FUNC LOCAL DEFAULT 1 al_mc_edac_irq_handler_ue
> 36: 00000278 56 FUNC LOCAL DEFAULT 1 al_mc_edac_check
> 37: 000002b0 680 FUNC LOCAL DEFAULT 1 al_mc_edac_probe
> 47: 00000000 20 FUNC LOCAL DEFAULT 3 al_mc_edac_driver_init
> 51: 00000000 12 FUNC LOCAL DEFAULT 5 al_mc_edac_driver_exit
> 53: 00000000 392 OBJECT LOCAL DEFAULT 16 al_mc_edac_of_match
> 59: 00000000 104 OBJECT LOCAL DEFAULT 20 al_mc_edac_driver
> 61: 00000000 0 FILE LOCAL DEFAULT ABS al_mc_edac.mod.c
> 88: 00000000 392 OBJECT GLOBAL DEFAULT 16 __mod_of__al_mc_edac_of_m
>
> Thx.
Thanks. shall be part of v10.
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

2020-08-16 12:54:22

by Shenhar, Talel

[permalink] [raw]
Subject: Re: [PATCH v9 2/2] EDAC: al-mc-edac: Introduce Amazon's Annapurna Labs Memory Controller EDAC


On 8/15/2020 9:33 PM, Borislav Petkov wrote:
> On Tue, Jul 28, 2020 at 12:51:55PM +0300, Talel Shenhar wrote:
>> +static void al_mc_edac_check(struct mem_ctl_info *mci)
>> +{
>> + struct al_mc_edac *al_mc = mci->pvt_info;
>> +
>> + if (al_mc->irq_ue <= 0)
>> + handle_ue(mci);
>> +
>> + if (al_mc->irq_ce <= 0)
>> + handle_ce(mci);
>> +}
>> +
>> +static irqreturn_t al_mc_edac_irq_handler_ue(int irq, void *info)
>> +{
>> + struct platform_device *pdev = info;
>> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
>> +
>> + if (handle_ue(mci))
>> + return IRQ_HANDLED;
>> + return IRQ_NONE;
>> +}
>> +
>> +static irqreturn_t al_mc_edac_irq_handler_ce(int irq, void *info)
>> +{
>> + struct platform_device *pdev = info;
>> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
>> +
>> + if (handle_ce(mci))
>> + return IRQ_HANDLED;
>> + return IRQ_NONE;
>> +}
>> +
>> +static enum scrub_type al_mc_edac_get_scrub_mode(void __iomem *mmio_base)
>> +{
>> + u32 ecccfg0;
>> +
>> + ecccfg0 = readl(mmio_base + AL_MC_ECC_CFG);
>> +
>> + if (FIELD_GET(AL_MC_ECC_CFG_SCRUB_DISABLED, ecccfg0))
>> + return SCRUB_NONE;
>> + else
>> + return SCRUB_HW_SRC;
>> +}
>> +
>> +static void devm_al_mc_edac_free(void *data)
>> +{
>> + edac_mc_free(data);
>> +}
>> +
>> +static void devm_al_mc_edac_del(void *data)
>> +{
>> + edac_mc_del_mc(data);
>> +}
> From a previous review:
>
> I said:
>
>> Drop the "al_mc_edac_" prefix from most of the static functions. You can
>> leave it in the probe function or the IRQ handler so that it is visible
>> in stack traces but all those small functions don't need that prefix.
> You replied with:
>
>> Shall be part of v7.
> and yet it ain't part of any v<num>.
>
> Why?

Thanks for taking a look.

From cover letter:

- removed static function names prefix from internal functions (external
  used function, such as devm/interrupts-handlers/probe, left with the
  prefix to allow stack trace visibility)

As you can see, part of the functions got their prefix removed, e.g.
prepare_msg, handle_ce, handle_ue.

I did take your advise for leaving prefix for having visibility for
functions being used outside. hence, some were left with the prefix.

Let me know what you think.

>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

2020-08-16 12:54:53

by Borislav Petkov

[permalink] [raw]
Subject: Re: [PATCH v9 2/2] EDAC: al-mc-edac: Introduce Amazon's Annapurna Labs Memory Controller EDAC

On Sun, Aug 16, 2020 at 12:17:31PM +0300, Shenhar, Talel wrote:
> Let me know what you think.

Well, devm_al_mc_edac_free() devm_al_mc_edac_del() look like useless
wrappers to me and can be removed and you can use edac_mc_del_mc() and
edac_mc_free() directly. But then you need to cast them in an ugly way
so that it builds:

ret = devm_add_action(&pdev->dev, (void (*)(void *data))edac_mc_free, mci);

I guess we can leave them as is and then lift them into the EDAC core if
someone else wants to do the same devm_* thing.

al_mc_edac_get_scrub_mode() doesn't need a prefix because it is used
only once and the compiler is simply inlining it so you can forget the
stack trace visibility:

$ readelf -s drivers/edac/al_mc_edac.ko | grep scrub
$

The others are fine, I guess, since they're function pointers and cannot be
inlined as such so you want them prefixed:

$ readelf -s drivers/edac/al_mc_edac.ko | grep al_mc_edac
23: 00000000 0 FILE LOCAL DEFAULT ABS al_mc_edac.c
25: 00000000 4 FUNC LOCAL DEFAULT 1 devm_al_mc_edac_free
27: 00000004 4 FUNC LOCAL DEFAULT 1 devm_al_mc_edac_del
31: 00000124 24 FUNC LOCAL DEFAULT 1 al_mc_edac_irq_handler_ce
35: 00000260 24 FUNC LOCAL DEFAULT 1 al_mc_edac_irq_handler_ue
36: 00000278 56 FUNC LOCAL DEFAULT 1 al_mc_edac_check
37: 000002b0 680 FUNC LOCAL DEFAULT 1 al_mc_edac_probe
47: 00000000 20 FUNC LOCAL DEFAULT 3 al_mc_edac_driver_init
51: 00000000 12 FUNC LOCAL DEFAULT 5 al_mc_edac_driver_exit
53: 00000000 392 OBJECT LOCAL DEFAULT 16 al_mc_edac_of_match
59: 00000000 104 OBJECT LOCAL DEFAULT 20 al_mc_edac_driver
61: 00000000 0 FILE LOCAL DEFAULT ABS al_mc_edac.mod.c
88: 00000000 392 OBJECT GLOBAL DEFAULT 16 __mod_of__al_mc_edac_of_m

Thx.

--
Regards/Gruss,
Boris.

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