[PATCH v10 3/3] edac: Introduce Amazon's Annapurna Labs L2 EDAC driver

From: Hanna Hawa
Date: Sun May 10 2020 - 11:14:29 EST

Introduce Amazon's Annapurna Labs L2 EDAC driver to detect and report L2
errors.

Signed-off-by: Hanna Hawa <hhhawa@xxxxxxxxxx>
---
MAINTAINERS | 5 +
drivers/edac/Kconfig | 8 ++
drivers/edac/Makefile | 1 +
drivers/edac/al_l2_edac.c | 273 ++++++++++++++++++++++++++++++++++++++
4 files changed, 287 insertions(+)
create mode 100644 drivers/edac/al_l2_edac.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a3ec6a1f7cae..da86c13e2719 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -806,6 +806,11 @@ M: Hanna Hawa <hhhawa@xxxxxxxxxx>
S: Maintained
F: drivers/edac/al_l1_edac.c

+AMAZON ANNAPURNA LABS L2 EDAC
+M: Hanna Hawa <hhhawa@xxxxxxxxxx>
+S: Maintained
+F: drivers/edac/al_l2_edac.c
+
AMAZON ANNAPURNA LABS THERMAL MMIO DRIVER
M: Talel Shenhar <talel@xxxxxxxxxx>
S: Maintained
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index ba280e9c37b3..501e4ccc15ea 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -82,6 +82,14 @@ config EDAC_AL_L1
for Amazon's Annapurna Labs SoCs.
This driver detects errors of L1 caches.

+config EDAC_AL_L2
+ tristate "Amazon's Annapurna Labs L2 EDAC"
+ depends on ARM64 && (ARCH_ALPINE || COMPILE_TEST)
+ help
+ Support for L2 error detection and correction
+ for Amazon's Annapurna Labs SoCs.
+ This driver detects errors of L2 caches.
+
config EDAC_AMD64
tristate "AMD64 (Opteron, Athlon64)"
depends on AMD_NB && EDAC_DECODE_MCE
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 5ceea270856c..9ea32bb97362 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -23,6 +23,7 @@ edac_mce_amd-y := mce_amd.o
obj-$(CONFIG_EDAC_DECODE_MCE) += edac_mce_amd.o

obj-$(CONFIG_EDAC_AL_L1) += al_l1_edac.o
+obj-$(CONFIG_EDAC_AL_L2) += al_l2_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_l2_edac.c b/drivers/edac/al_l2_edac.c
new file mode 100644
index 000000000000..c22efacc4114
--- /dev/null
+++ b/drivers/edac/al_l2_edac.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/cpumask.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/smp.h>
+#include <asm/sysreg.h>
+
+#include "edac_device.h"
+#include "edac_module.h"
+
+#define DRV_NAME "al_l2_edac"
+
+/* Same bit assignments of L2MERRSR_EL1 in ARM CA57/CA72 */
+#define ARM_CA57_L2MERRSR_EL1 sys_reg(3, 1, 15, 2, 3)
+#define ARM_CA57_L2MERRSR_RAMID GENMASK(30, 24)
+#define ARM_CA57_L2_TAG_RAM 0x10
+#define ARM_CA57_L2_DATA_RAM 0x11
+#define ARM_CA57_L2_SNOOP_RAM 0x12
+#define ARM_CA57_L2_DIRTY_RAM 0x14
+#define ARM_CA57_L2_INC_PF_RAM 0x18
+#define ARM_CA57_L2MERRSR_VALID BIT(31)
+#define ARM_CA57_L2MERRSR_REPEAT GENMASK_ULL(39, 32)
+#define ARM_CA57_L2MERRSR_OTHER GENMASK_ULL(47, 40)
+#define ARM_CA57_L2MERRSR_FATAL BIT_ULL(63)
+
+#define AL_L2_EDAC_MSG_MAX 256
+
+struct al_l2_cache {
+ cpumask_t cluster_cpus;
+ struct list_head list_node;
+ struct device_node *of_node;
+};
+
+struct al_l2_edac {
+ struct list_head l2_caches;
+ spinlock_t lock;
+};
+
+static struct platform_device *edac_l2_device;
+
+static void l2merrsr_read_status(void *arg)
+{
+ struct edac_device_ctl_info *edac_dev = arg;
+ u32 ramid, repeat, other, fatal;
+ char msg[AL_L2_EDAC_MSG_MAX];
+ struct al_l2_edac *al_l2;
+ int cpu, space, count;
+ u64 val;
+ char *p;
+
+ al_l2 = edac_dev->pvt_info;
+
+ val = read_sysreg_s(ARM_CA57_L2MERRSR_EL1);
+ if (!(FIELD_GET(ARM_CA57_L2MERRSR_VALID, val)))
+ return;
+
+ write_sysreg_s(0, ARM_CA57_L2MERRSR_EL1);
+
+ cpu = smp_processor_id();
+ ramid = FIELD_GET(ARM_CA57_L2MERRSR_RAMID, val);
+ repeat = FIELD_GET(ARM_CA57_L2MERRSR_REPEAT, val);
+ other = FIELD_GET(ARM_CA57_L2MERRSR_OTHER, val);
+ fatal = FIELD_GET(ARM_CA57_L2MERRSR_FATAL, val);
+
+ space = sizeof(msg);
+ p = msg;
+ count = scnprintf(p, space, "CPU%d L2 %serror detected", cpu,
+ (fatal) ? "Fatal " : "");
+ p += count;
+ space -= count;
+
+ switch (ramid) {
+ case ARM_CA57_L2_TAG_RAM:
+ count = scnprintf(p, space, " RAMID='L2 Tag RAM'");
+ break;
+ case ARM_CA57_L2_DATA_RAM:
+ count = scnprintf(p, space, " RAMID='L2 Data RAM'");
+ break;
+ case ARM_CA57_L2_SNOOP_RAM:
+ count = scnprintf(p, space, " RAMID='L2 Snoop Tag RAM'");
+ break;
+ case ARM_CA57_L2_DIRTY_RAM:
+ count = scnprintf(p, space, " RAMID='L2 Dirty RAM'");
+ break;
+ case ARM_CA57_L2_INC_PF_RAM:
+ count = scnprintf(p, space, " RAMID='L2 internal metadata'");
+ break;
+ default:
+ count = scnprintf(p, space, " RAMID='unknown'");
+ break;
+ }
+
+ p += count;
+ space -= count;
+
+ count = scnprintf(p, space,
+ " repeat=%d, other=%d (L2MERRSR_EL1=0x%llx)",
+ repeat, other, val);
+
+ spin_lock(&al_l2->lock);
+ if (fatal)
+ edac_device_handle_ue_count(edac_dev, repeat, 0, 0, msg);
+ else
+ edac_device_handle_ce_count(edac_dev, repeat, 0, 0, msg);
+ spin_unlock(&al_l2->lock);
+}
+
+static void al_l2_edac_check(struct edac_device_ctl_info *edac_dev)
+{
+ struct al_l2_edac *al_l2 = edac_dev->pvt_info;
+ struct al_l2_cache *l2_cache;
+
+ list_for_each_entry(l2_cache, &al_l2->l2_caches, list_node)
+ smp_call_function_any(&l2_cache->cluster_cpus,
+ al_l2_edac_l2merrsr_read_status,
+ edac_dev, 1);
+}
+
+static int al_l2_edac_probe(struct platform_device *pdev)
+{
+ struct edac_device_ctl_info *edac_dev;
+ struct device *dev = &pdev->dev;
+ struct al_l2_cache *l2_cache;
+ struct al_l2_edac *al_l2;
+ int ret, i;
+
+ edac_dev = edac_device_alloc_ctl_info(sizeof(*al_l2), DRV_NAME, 1, "L",
+ 1, 2, NULL, 0,
+ edac_device_alloc_index());
+ if (!edac_dev)
+ return -ENOMEM;
+
+ al_l2 = edac_dev->pvt_info;
+ edac_dev->edac_check = al_l2_edac_check;
+ edac_dev->dev = dev;
+ edac_dev->mod_name = DRV_NAME;
+ edac_dev->dev_name = dev_name(dev);
+ edac_dev->ctl_name = "L2_cache";
+ platform_set_drvdata(pdev, edac_dev);
+
+ spin_lock_init(&al_l2->lock);
+ INIT_LIST_HEAD(&al_l2->l2_caches);
+
+ for_each_possible_cpu(i) {
+ struct device_node *cpu;
+ struct device_node *cpu_cache;
+ bool found = false;
+
+ cpu = of_get_cpu_node(i, NULL);
+ if (!cpu)
+ continue;
+
+ cpu_cache = of_find_next_cache_node(cpu);
+ list_for_each_entry(l2_cache, &al_l2->l2_caches, list_node) {
+ if (l2_cache->of_node == cpu_cache) {
+ found = true;
+ break;
+ }
+ }
+
+ if (found) {
+ cpumask_set_cpu(i, &l2_cache->cluster_cpus);
+ of_node_put(cpu_cache);
+ } else {
+ l2_cache = devm_kzalloc(dev, sizeof(*l2_cache),
+ GFP_KERNEL);
+ l2_cache->of_node = cpu_cache;
+ list_add(&l2_cache->list_node, &al_l2->l2_caches);
+ cpumask_set_cpu(i, &l2_cache->cluster_cpus);
+ }
+
+ of_node_put(cpu);
+ }
+
+ list_for_each_entry(l2_cache, &al_l2->l2_caches, list_node)
+ of_node_put(l2_cache->of_node);
+
+ if (list_empty(&al_l2->l2_caches)) {
+ dev_err(dev, "L2 Cache list is empty for EDAC device\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ ret = edac_device_add_device(edac_dev);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ dev_err(dev, "Failed to add L2 edac device (%d)\n", ret);
+ edac_device_free_ctl_info(edac_dev);
+
+ return ret;
+}
+
+static int al_l2_edac_remove(struct platform_device *pdev)
+{
+ struct edac_device_ctl_info *edac_dev = platform_get_drvdata(pdev);
+
+ edac_device_del_device(edac_dev->dev);
+ edac_device_free_ctl_info(edac_dev);
+
+ return 0;
+}
+
+static const struct of_device_id al_l2_edac_of_match[] = {
+ /*
+ * "al,alpine-v2", and "amazon,al-alpine-v3" are machine compatible
+ * strings which have Cortex-A57/A72 configured with this support,
+ * and access to L2MERRSR_EL1 register is enabled in firmware.
+ */
+ { .compatible = "al,alpine-v2" },
+ { .compatible = "amazon,al-alpine-v3" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, al_l2_edac_of_match);
+
+static struct platform_driver al_l2_edac_driver = {
+ .probe = al_l2_edac_probe,
+ .remove = al_l2_edac_remove,
+ .driver = {
+ .name = DRV_NAME,
+ },
+};
+
+static int __init al_l2_init(void)
+{
+ struct device_node *root;
+ int ret;
+
+ root = of_find_node_by_path("/");
+ if (!root) {
+ pr_debug("Can't find root node!\n");
+ return 0;
+ }
+
+ if (!of_match_node(al_l2_edac_of_match, root))
+ return 0;
+
+ ret = platform_driver_register(&al_l2_edac_driver);
+ if (ret) {
+ pr_err("Failed to register %s (%d)\n", DRV_NAME, ret);
+ return ret;
+ }
+
+ edac_l2_device = platform_device_register_simple(DRV_NAME, -1, NULL, 0);
+ if (IS_ERR(edac_l2_device)) {
+ pr_err("Failed to register EDAC AL L2 platform device\n");
+ platform_driver_unregister(&al_l2_edac_driver);
+ return PTR_ERR(edac_l2_device);
+ }
+
+ return 0;
+}
+
+static void __exit al_l2_exit(void)
+{
+ platform_device_unregister(edac_l2_device);
+ platform_driver_unregister(&al_l2_edac_driver);
+}
+
+module_init(al_l2_init);
+module_exit(al_l2_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Hanna Hawa <hhhawa@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Amazon's Annapurna Lab's L2 EDAC Driver");
--
2.17.1