[RFC PATCH 1/4] cxl: Register devices for CXL Hotness Monitoring Units (CHMU)
From: Jonathan Cameron
Date: Thu Nov 21 2024 - 05:22:24 EST
Basic registration using similar approach to how the CPMUs
are registered.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
drivers/cxl/core/Makefile | 1 +
drivers/cxl/core/hmu.c | 64 +++++++++++++++++++++++++++++++++++++++
drivers/cxl/core/regs.c | 14 +++++++++
drivers/cxl/cxl.h | 4 +++
drivers/cxl/cxlpci.h | 1 +
drivers/cxl/hmu.h | 23 ++++++++++++++
drivers/cxl/pci.c | 26 +++++++++++++++-
7 files changed, 132 insertions(+), 1 deletion(-)
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index 9259bcc6773c..d060abb773ae 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -12,6 +12,7 @@ cxl_core-y += memdev.o
cxl_core-y += mbox.o
cxl_core-y += pci.o
cxl_core-y += hdm.o
+cxl_core-y += hmu.o
cxl_core-y += pmu.o
cxl_core-y += cdat.o
cxl_core-$(CONFIG_TRACING) += trace.o
diff --git a/drivers/cxl/core/hmu.c b/drivers/cxl/core/hmu.c
new file mode 100644
index 000000000000..3ee938bb6c05
--- /dev/null
+++ b/drivers/cxl/core/hmu.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2024 Huawei. All rights reserved. */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <cxlmem.h>
+#include <hmu.h>
+#include <cxl.h>
+#include "core.h"
+
+static void cxl_hmu_release(struct device *dev)
+{
+ struct cxl_hmu *hmu = to_cxl_hmu(dev);
+
+ kfree(hmu);
+}
+
+const struct device_type cxl_hmu_type = {
+ .name = "cxl_hmu",
+ .release = cxl_hmu_release,
+};
+
+static void remove_dev(void *dev)
+{
+ device_unregister(dev);
+}
+
+int devm_cxl_hmu_add(struct device *parent, struct cxl_hmu_regs *regs,
+ int assoc_id, int index)
+{
+ struct cxl_hmu *hmu;
+ struct device *dev;
+ int rc;
+
+ hmu = kzalloc(sizeof(*hmu), GFP_KERNEL);
+ if (!hmu)
+ return -ENOMEM;
+
+ hmu->assoc_id = assoc_id;
+ hmu->index = index;
+ hmu->base = regs->hmu;
+ dev = &hmu->dev;
+ device_initialize(dev);
+ device_set_pm_not_required(dev);
+ dev->parent = parent;
+ dev->bus = &cxl_bus_type;
+ dev->type = &cxl_hmu_type;
+ rc = dev_set_name(dev, "hmu_mem%d.%d", assoc_id, index);
+ if (rc)
+ goto err;
+
+ rc = device_add(dev);
+ if (rc)
+ goto err;
+
+ return devm_add_action_or_reset(parent, remove_dev, dev);
+
+err:
+ put_device(&hmu->dev);
+ return rc;
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxl_hmu_add, CXL);
+
diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c
index e1082e749c69..c12afaa6ef98 100644
--- a/drivers/cxl/core/regs.c
+++ b/drivers/cxl/core/regs.c
@@ -401,6 +401,20 @@ int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs)
}
EXPORT_SYMBOL_NS_GPL(cxl_map_pmu_regs, CXL);
+int cxl_map_hmu_regs(struct cxl_register_map *map, struct cxl_hmu_regs *regs)
+{
+ struct device *dev = map->host;
+ resource_size_t phys_addr;
+
+ phys_addr = map->resource;
+ regs->hmu = devm_cxl_iomap_block(dev, phys_addr, map->max_size);
+ if (!regs->hmu)
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_map_hmu_regs, CXL);
+
static int cxl_map_regblock(struct cxl_register_map *map)
{
struct device *host = map->host;
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 5406e3ab3d4a..8172bc1f7a8d 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -227,6 +227,9 @@ struct cxl_regs {
struct_group_tagged(cxl_pmu_regs, pmu_regs,
void __iomem *pmu;
);
+ struct_group_tagged(cxl_hmu_regs, hmu_regs,
+ void __iomem *hmu;
+ );
/*
* RCH downstream port specific RAS register
@@ -292,6 +295,7 @@ int cxl_map_component_regs(const struct cxl_register_map *map,
unsigned long map_mask);
int cxl_map_device_regs(const struct cxl_register_map *map,
struct cxl_device_regs *regs);
+int cxl_map_hmu_regs(struct cxl_register_map *map, struct cxl_hmu_regs *regs);
int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs);
enum cxl_regloc_type;
diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
index 4da07727ab9c..71f5e9620137 100644
--- a/drivers/cxl/cxlpci.h
+++ b/drivers/cxl/cxlpci.h
@@ -67,6 +67,7 @@ enum cxl_regloc_type {
CXL_REGLOC_RBI_VIRT,
CXL_REGLOC_RBI_MEMDEV,
CXL_REGLOC_RBI_PMU,
+ CXL_REGLOC_RBI_HMU,
CXL_REGLOC_RBI_TYPES
};
diff --git a/drivers/cxl/hmu.h b/drivers/cxl/hmu.h
new file mode 100644
index 000000000000..c4798ed9764b
--- /dev/null
+++ b/drivers/cxl/hmu.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright(c) 2024 Huawei
+ * CXL Specification rev 3.2 Setion 8.2.8 (CHMU Register Interface)
+ */
+#ifndef CXL_HMU_H
+#define CXL_HMU_H
+#include <linux/device.h>
+
+#define CXL_HMU_REGMAP_SIZE 0xe00 /* Table 8-32 CXL 3.0 specification */
+struct cxl_hmu {
+ struct device dev;
+ void __iomem *base;
+ int assoc_id;
+ int index;
+};
+
+#define to_cxl_hmu(dev) container_of(dev, struct cxl_hmu, dev)
+struct cxl_hmu_regs;
+int devm_cxl_hmu_add(struct device *parent, struct cxl_hmu_regs *regs,
+ int assoc_id, int idx);
+
+#endif
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 188412d45e0d..e89ea9d3f007 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -15,6 +15,7 @@
#include "cxlmem.h"
#include "cxlpci.h"
#include "cxl.h"
+#include "hmu.h"
#include "pmu.h"
/**
@@ -814,7 +815,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
struct cxl_dev_state *cxlds;
struct cxl_register_map map;
struct cxl_memdev *cxlmd;
- int i, rc, pmu_count;
+ int i, rc, hmu_count, pmu_count;
bool irq_avail;
/*
@@ -938,6 +939,29 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
}
}
+ hmu_count = cxl_count_regblock(pdev, CXL_REGLOC_RBI_HMU);
+ for (i = 0; i < hmu_count; i++) {
+ struct cxl_hmu_regs hmu_regs;
+
+ rc = cxl_find_regblock_instance(pdev, CXL_REGLOC_RBI_HMU, &map, i);
+ if (rc) {
+ dev_dbg(&pdev->dev, "Could not find HMU regblock\n");
+ break;
+ }
+
+ rc = cxl_map_hmu_regs(&map, &hmu_regs);
+ if (rc) {
+ dev_dbg(&pdev->dev, "Could not map HMU regs\n");
+ break;
+ }
+
+ rc = devm_cxl_hmu_add(cxlds->dev, &hmu_regs, cxlmd->id, i);
+ if (rc) {
+ dev_dbg(&pdev->dev, "Could not add HMU instance\n");
+ break;
+ }
+ }
+
rc = cxl_event_config(host_bridge, mds, irq_avail);
if (rc)
return rc;
--
2.43.0