From: "Alastair D'Silva" <alastair@au1.ibm.com>
To: alastair@d-silva.org
Cc: "Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
"Paul Mackerras" <paulus@samba.org>,
"Michael Ellerman" <mpe@ellerman.id.au>,
"Frederic Barrat" <fbarrat@linux.ibm.com>,
"Andrew Donnellan" <ajd@linux.ibm.com>,
"Arnd Bergmann" <arnd@arndb.de>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"Dan Williams" <dan.j.williams@intel.com>,
"Vishal Verma" <vishal.l.verma@intel.com>,
"Dave Jiang" <dave.jiang@intel.com>,
"Keith Busch" <keith.busch@intel.com>,
"Ira Weiny" <ira.weiny@intel.com>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Mauro Carvalho Chehab" <mchehab+samsung@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
"Rob Herring" <robh@kernel.org>,
"Anton Blanchard" <anton@ozlabs.org>,
"Krzysztof Kozlowski" <krzk@kernel.org>,
"Mahesh Salgaonkar" <mahesh@linux.vnet.ibm.com>,
"Madhavan Srinivasan" <maddy@linux.vnet.ibm.com>,
"Cédric Le Goater" <clg@kaod.org>,
"Anju T Sudhakar" <anju@linux.vnet.ibm.com>,
"Hari Bathini" <hbathini@linux.ibm.com>,
"Thomas Gleixner" <tglx@linutronix.de>,
"Greg Kurz" <groug@kaod.org>,
"Nicholas Piggin" <npiggin@gmail.com>,
"Masahiro Yamada" <yamada.masahiro@socionext.com>,
"Alexey Kardashevskiy" <aik@ozlabs.ru>,
linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-nvdimm@lists.01.org, linux-mm@kvack.org
Subject: [PATCH v2 19/27] nvdimm/ocxl: Forward events to userspace
Date: Tue, 3 Dec 2019 14:46:47 +1100 [thread overview]
Message-ID: <20191203034655.51561-20-alastair@au1.ibm.com> (raw)
In-Reply-To: <20191203034655.51561-1-alastair@au1.ibm.com>
From: Alastair D'Silva <alastair@d-silva.org>
Some of the interrupts that the card generates are better handled
by the userspace daemon, in particular:
Controller Hardware/Firmware Fatal
Controller Dump Available
Error Log available
This patch allows a userspace application to register an eventfd with
the driver via SCM_IOCTL_EVENTFD to receive notifications of these
interrupts.
Userspace can then identify what events have occurred by calling
SCM_IOCTL_EVENT_CHECK and checking against the SCM_IOCTL_EVENT_FOO
masks.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
---
drivers/nvdimm/ocxl/scm.c | 216 +++++++++++++++++++++++++++++
drivers/nvdimm/ocxl/scm_internal.h | 5 +
include/uapi/nvdimm/ocxl-scm.h | 16 +++
3 files changed, 237 insertions(+)
diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
index 54a2bac1cab7..854787950334 100644
--- a/drivers/nvdimm/ocxl/scm.c
+++ b/drivers/nvdimm/ocxl/scm.c
@@ -9,6 +9,7 @@
#include <misc/ocxl.h>
#include <linux/delay.h>
#include <linux/ndctl.h>
+#include <linux/eventfd.h>
#include <linux/fs.h>
#include <linux/mm_types.h>
#include <linux/memory_hotplug.h>
@@ -382,11 +383,22 @@ static void free_scm(struct scm_data *scm_data)
{
int rc;
+ // Disable doorbells
+ (void)ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_CHIEC,
+ OCXL_LITTLE_ENDIAN,
+ GLOBAL_MMIO_CHI_ALL);
+
if (scm_data->nvdimm_bus)
nvdimm_bus_unregister(scm_data->nvdimm_bus);
free_scm_minor(scm_data);
+ if (scm_data->irq_addr[1])
+ iounmap(scm_data->irq_addr[1]);
+
+ if (scm_data->irq_addr[0])
+ iounmap(scm_data->irq_addr[0]);
+
if (scm_data->cdev.owner)
cdev_del(&scm_data->cdev);
@@ -491,6 +503,11 @@ static int scm_file_release(struct inode *inode, struct file *file)
{
struct scm_data *scm_data = file->private_data;
+ if (scm_data->ev_ctx) {
+ eventfd_ctx_put(scm_data->ev_ctx);
+ scm_data->ev_ctx = NULL;
+ }
+
scm_put(scm_data);
return 0;
}
@@ -986,6 +1003,51 @@ static int scm_ioctl_controller_stats(struct scm_data *scm_data,
return rc;
}
+static int scm_ioctl_eventfd(struct scm_data *scm_data,
+ struct scm_ioctl_eventfd __user *uarg)
+{
+ struct scm_ioctl_eventfd args;
+
+ if (copy_from_user(&args, uarg, sizeof(args)))
+ return -EFAULT;
+
+ if (scm_data->ev_ctx)
+ return -EINVAL;
+
+ scm_data->ev_ctx = eventfd_ctx_fdget(args.eventfd);
+ if (!scm_data->ev_ctx)
+ return -EFAULT;
+
+ return 0;
+}
+
+static int scm_ioctl_event_check(struct scm_data *scm_data, u64 __user *uarg)
+{
+ u64 val = 0;
+ int rc;
+ u64 chi = 0;
+
+ rc = scm_chi(scm_data, &chi);
+ if (rc < 0)
+ return rc;
+
+ if (chi & GLOBAL_MMIO_CHI_ELA)
+ val |= SCM_IOCTL_EVENT_ERROR_LOG_AVAILABLE;
+
+ if (chi & GLOBAL_MMIO_CHI_CDA)
+ val |= SCM_IOCTL_EVENT_CONTROLLER_DUMP_AVAILABLE;
+
+ if (chi & GLOBAL_MMIO_CHI_CFFS)
+ val |= SCM_IOCTL_EVENT_FIRMWARE_FATAL;
+
+ if (chi & GLOBAL_MMIO_CHI_CHFS)
+ val |= SCM_IOCTL_EVENT_HARDWARE_FATAL;
+
+ rc = copy_to_user((u64 __user *) uarg, &val, sizeof(val));
+
+ return rc;
+}
+
static long scm_file_ioctl(struct file *file, unsigned int cmd,
unsigned long args)
{
@@ -1015,6 +1077,15 @@ static long scm_file_ioctl(struct file *file, unsigned int cmd,
rc = scm_ioctl_controller_stats(scm_data,
(struct scm_ioctl_controller_stats __user *)args);
break;
+
+ case SCM_IOCTL_EVENTFD:
+ rc = scm_ioctl_eventfd(scm_data,
+ (struct scm_ioctl_eventfd __user *)args);
+ break;
+
+ case SCM_IOCTL_EVENT_CHECK:
+ rc = scm_ioctl_event_check(scm_data, (u64 __user *)args);
+ break;
}
return rc;
@@ -1156,6 +1227,146 @@ static void scm_dump_error_log(struct scm_data *scm_data)
kfree(buf);
}
+static irqreturn_t scm_imn0_handler(void *private)
+{
+ struct scm_data *scm_data = private;
+ u64 chi = 0;
+
+ (void)scm_chi(scm_data, &chi);
+
+ if (chi & GLOBAL_MMIO_CHI_ELA) {
+ dev_warn(&scm_data->dev, "Error log is available\n");
+
+ if (scm_data->ev_ctx)
+ eventfd_signal(scm_data->ev_ctx, 1);
+ }
+
+ if (chi & GLOBAL_MMIO_CHI_CDA) {
+ dev_warn(&scm_data->dev, "Controller dump is available\n");
+
+ if (scm_data->ev_ctx)
+ eventfd_signal(scm_data->ev_ctx, 1);
+ }
+
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t scm_imn1_handler(void *private)
+{
+ struct scm_data *scm_data = private;
+ u64 chi = 0;
+
+ (void)scm_chi(scm_data, &chi);
+
+ if (chi & (GLOBAL_MMIO_CHI_CFFS | GLOBAL_MMIO_CHI_CHFS)) {
+ dev_err(&scm_data->dev,
+ "Controller status is fatal, chi=0x%llx, going offline\n", chi);
+
+ if (scm_data->nvdimm_bus) {
+ nvdimm_bus_unregister(scm_data->nvdimm_bus);
+ scm_data->nvdimm_bus = NULL;
+ }
+
+ if (scm_data->ev_ctx)
+ eventfd_signal(scm_data->ev_ctx, 1);
+ }
+
+ return IRQ_HANDLED;
+}
+
+
+/**
+ * scm_setup_irq() - Set up the IRQs for the SCM device
+ * @scm_data: the SCM metadata
+ * Return: 0 on success, negative on failure
+ */
+static int scm_setup_irq(struct scm_data *scm_data)
+{
+ int rc;
+ u64 irq_addr;
+
+ rc = ocxl_afu_irq_alloc(scm_data->ocxl_context, &scm_data->irq_id[0]);
+ if (rc)
+ return rc;
+
+ rc = ocxl_irq_set_handler(scm_data->ocxl_context, scm_data->irq_id[0],
+ scm_imn0_handler, NULL, scm_data);
+
+ irq_addr = ocxl_afu_irq_get_addr(scm_data->ocxl_context, scm_data->irq_id[0]);
+ if (!irq_addr)
+ return -EINVAL;
+
+ scm_data->irq_addr[0] = ioremap(irq_addr, PAGE_SIZE);
+ if (!scm_data->irq_addr[0])
+ return -EINVAL;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu, GLOBAL_MMIO_IMA0_OHP,
+ OCXL_LITTLE_ENDIAN,
+ (u64)scm_data->irq_addr[0]);
+ if (rc)
+ goto out_irq0;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu, GLOBAL_MMIO_IMA0_CFP,
+ OCXL_LITTLE_ENDIAN, 0);
+ if (rc)
+ goto out_irq0;
+
+ rc = ocxl_afu_irq_alloc(scm_data->ocxl_context, &scm_data->irq_id[1]);
+ if (rc)
+ goto out_irq0;
+
+
+ rc = ocxl_irq_set_handler(scm_data->ocxl_context, scm_data->irq_id[1],
+ scm_imn1_handler, NULL, scm_data);
+ if (rc)
+ goto out_irq0;
+
+ irq_addr = ocxl_afu_irq_get_addr(scm_data->ocxl_context, scm_data->irq_id[1]);
+ if (!irq_addr) {
+ rc = -EFAULT;
+ goto out_irq0;
+ }
+
+ scm_data->irq_addr[1] = ioremap(irq_addr, PAGE_SIZE);
+ if (!scm_data->irq_addr[1]) {
+ rc = -EINVAL;
+ goto out_irq0;
+ }
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu, GLOBAL_MMIO_IMA1_OHP,
+ OCXL_LITTLE_ENDIAN,
+ (u64)scm_data->irq_addr[1]);
+ if (rc)
+ goto out_irq1;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu, GLOBAL_MMIO_IMA1_CFP,
+ OCXL_LITTLE_ENDIAN, 0);
+ if (rc)
+ goto out_irq1;
+
+ // Enable doorbells
+ rc = ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_CHIE,
+ OCXL_LITTLE_ENDIAN,
+ GLOBAL_MMIO_CHI_ELA | GLOBAL_MMIO_CHI_CDA |
+ GLOBAL_MMIO_CHI_CFFS | GLOBAL_MMIO_CHI_CHFS |
+ GLOBAL_MMIO_CHI_NSCRA);
+ if (rc)
+ goto out_irq1;
+
+ return 0;
+
+out_irq1:
+ iounmap(scm_data->irq_addr[1]);
+ scm_data->irq_addr[1] = NULL;
+
+out_irq0:
+ iounmap(scm_data->irq_addr[0]);
+ scm_data->irq_addr[0] = NULL;
+
+ return rc;
+}
+
/**
* scm_probe_function_0 - Set up function 0 for an OpenCAPI Storage Class Memory device
* This is important as it enables templates higher than 0 across all other functions,
@@ -1261,6 +1472,11 @@ static int scm_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
goto err;
}
+ if (scm_setup_irq(scm_data)) {
+ dev_err(&pdev->dev, "Could not set up OCXL IRQs for SCM\n");
+ goto err;
+ }
+
if (scm_setup_command_metadata(scm_data)) {
dev_err(&pdev->dev, "Could not read OCXL command matada\n");
goto err;
diff --git a/drivers/nvdimm/ocxl/scm_internal.h b/drivers/nvdimm/ocxl/scm_internal.h
index 9bf8fcf30ea6..693fd59f8bde 100644
--- a/drivers/nvdimm/ocxl/scm_internal.h
+++ b/drivers/nvdimm/ocxl/scm_internal.h
@@ -104,6 +104,10 @@ struct scm_data {
struct pci_dev *pdev;
struct cdev cdev;
struct ocxl_fn *ocxl_fn;
+#define SCM_IRQ_COUNT 2
+ int irq_id[SCM_IRQ_COUNT];
+ struct dev_pagemap irq_pgmap[SCM_IRQ_COUNT];
+ void *irq_addr[SCM_IRQ_COUNT];
struct nd_interleave_set nd_set;
struct nvdimm_bus_descriptor bus_desc;
struct nvdimm_bus *nvdimm_bus;
@@ -114,6 +118,7 @@ struct scm_data {
struct command_metadata ns_command;
struct resource scm_res;
struct nd_region *nd_region;
+ struct eventfd_ctx *ev_ctx;
char fw_version[8+1];
u32 timeouts[ADMIN_COMMAND_MAX+1];
diff --git a/include/uapi/nvdimm/ocxl-scm.h b/include/uapi/nvdimm/ocxl-scm.h
index 0a5de46c5acd..e86ffb02d31f 100644
--- a/include/uapi/nvdimm/ocxl-scm.h
+++ b/include/uapi/nvdimm/ocxl-scm.h
@@ -66,6 +66,20 @@ struct scm_ioctl_controller_stats {
__u64 cache_write_latency; // nanoseconds
};
+struct scm_ioctl_eventfd {
+ __s32 eventfd;
+ __u32 reserved;
+};
+
+#ifndef BIT_ULL
+#define BIT_ULL(nr) (1ULL << (nr))
+#endif
+
+#define SCM_IOCTL_EVENT_CONTROLLER_DUMP_AVAILABLE BIT_ULL(0)
+#define SCM_IOCTL_EVENT_ERROR_LOG_AVAILABLE BIT_ULL(1)
+#define SCM_IOCTL_EVENT_HARDWARE_FATAL BIT_ULL(2)
+#define SCM_IOCTL_EVENT_FIRMWARE_FATAL BIT_ULL(3)
+
/* ioctl numbers */
#define SCM_MAGIC 0x5C
/* SCM devices */
@@ -74,5 +88,7 @@ struct scm_ioctl_controller_stats {
#define SCM_IOCTL_CONTROLLER_DUMP_DATA _IOWR(SCM_MAGIC, 0x03, struct scm_ioctl_controller_dump_data)
#define SCM_IOCTL_CONTROLLER_DUMP_COMPLETE _IO(SCM_MAGIC, 0x04)
#define SCM_IOCTL_CONTROLLER_STATS _IO(SCM_MAGIC, 0x05)
+#define SCM_IOCTL_EVENTFD _IOW(SCM_MAGIC, 0x06, struct scm_ioctl_eventfd)
+#define SCM_IOCTL_EVENT_CHECK _IOR(SCM_MAGIC, 0x07, __u64)
#endif /* _UAPI_OCXL_SCM_H */
--
2.23.0
next prev parent reply other threads:[~2019-12-03 3:48 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-03 3:46 [PATCH v2 00/27] Add support for OpenCAPI SCM devices Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 01/27] memory_hotplug: Add a bounds check to __add_pages Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 02/27] nvdimm: remove prototypes for nonexistent functions Alastair D'Silva
2019-12-03 4:47 ` Andrew Donnellan
2019-12-04 0:10 ` Dan Williams
2020-01-23 21:49 ` Dan Williams
2019-12-03 3:46 ` [PATCH v2 03/27] powerpc: Add OPAL calls for LPC memory alloc/release Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 04/27] mm/memory_hotplug: Allow check_hotplug_memory_addressable to be called from drivers Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 05/27] powerpc: Map & release OpenCAPI LPC memory Alastair D'Silva
2020-01-09 14:41 ` Frederic Barrat
2020-01-21 6:46 ` Andrew Donnellan
2020-01-21 7:11 ` Greg Kurz
2020-02-14 11:09 ` Frederic Barrat
2020-02-18 23:44 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 06/27] ocxl: Tally up the LPC memory on a link & allow it to be mapped Alastair D'Silva
2020-01-09 14:48 ` Frederic Barrat
2020-02-03 12:37 ` Jonathan Cameron
2020-02-19 0:01 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 07/27] ocxl: Add functions to map/unmap LPC memory Alastair D'Silva
2020-01-09 14:49 ` Frederic Barrat
2020-02-03 12:49 ` Jonathan Cameron
2020-02-19 2:39 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 08/27] ocxl: Save the device serial number in ocxl_fn Alastair D'Silva
2020-02-03 12:53 ` Jonathan Cameron
2020-02-19 4:03 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 09/27] ocxl: Free detached contexts in ocxl_context_detach_all() Alastair D'Silva
2020-01-09 14:54 ` Frederic Barrat
2019-12-03 3:46 ` [PATCH v2 10/27] nvdimm: Add driver for OpenCAPI Storage Class Memory Alastair D'Silva
2019-12-03 5:05 ` Alastair D'Silva
2020-02-03 13:20 ` Jonathan Cameron
2020-02-19 4:40 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 11/27] nvdimm/ocxl: Add register addresses & status values to header Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 12/27] nvdimm/ocxl: Read the capability registers & wait for device ready Alastair D'Silva
2020-02-03 13:23 ` Jonathan Cameron
2020-02-19 4:46 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 13/27] nvdimm/ocxl: Add support for Admin commands Alastair D'Silva
2020-02-03 14:18 ` Jonathan Cameron
2020-02-19 5:00 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 14/27] nvdimm/ocxl: Add support for near storage commands Alastair D'Silva
2020-02-03 14:22 ` Jonathan Cameron
2020-02-19 4:54 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 15/27] nvdimm/ocxl: Register a character device for userspace to interact with Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 16/27] nvdimm/ocxl: Implement the Read Error Log command Alastair D'Silva
2019-12-05 3:42 ` Alastair D'Silva
2019-12-05 19:34 ` kbuild test robot
2019-12-03 3:46 ` [PATCH v2 17/27] nvdimm/ocxl: Add controller dump IOCTLs Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 18/27] nvdimm/ocxl: Add an IOCTL to report controller statistics Alastair D'Silva
2019-12-03 3:46 ` Alastair D'Silva [this message]
2019-12-03 3:46 ` [PATCH v2 20/27] nvdimm/ocxl: Add an IOCTL to request controller health & perf data Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 21/27] nvdimm/ocxl: Support firmware update via sysfs Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 22/27] nvdimm/ocxl: Implement the heartbeat command Alastair D'Silva
2020-02-03 15:11 ` Jonathan Cameron
2020-02-19 5:02 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 23/27] nvdimm/ocxl: Add debug IOCTLs Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 24/27] nvdimm/ocxl: Implement Overwrite Alastair D'Silva
2020-02-03 15:10 ` Jonathan Cameron
2020-02-19 5:13 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 25/27] nvdimm/ocxl: Expose SMART data via ndctl Alastair D'Silva
2019-12-16 0:15 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 26/27] powerpc: Enable OpenCAPI Storage Class Memory driver on bare metal Alastair D'Silva
2019-12-03 4:54 ` Andrew Donnellan
2019-12-03 4:57 ` Alastair D'Silva
2019-12-03 3:46 ` [PATCH v2 27/27] MAINTAINERS: Add myself & nvdimm/ocxl to ocxl Alastair D'Silva
2019-12-03 3:50 ` [PATCH v2 00/27] Add support for OpenCAPI SCM devices Matthew Wilcox
2019-12-03 4:01 ` Alastair D'Silva
2019-12-03 12:42 ` Matthew Wilcox
2019-12-04 0:15 ` Dan Williams
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