[PATCH v5 09/34] misc: xlink-pcie: lh: Add PCIe EPF driver for Local Host

mgross
2021-02-06T04:41:33Z

From: Srikanth Thokala <srikanth.thokala@intel.com>

Add PCIe EPF driver for local host (lh) to configure BAR's and other
HW resources. Underlying PCIe HW controller is a Synopsys DWC PCIe core.

Cc: Derek Kiernan <derek.kiernan@xilinx.com>
Cc: Dragan Cvetic <dragan.cvetic@xilinx.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Srikanth Thokala <srikanth.thokala@intel.com>
---
MAINTAINERS | 6 +
drivers/misc/Kconfig | 1 +
drivers/misc/Makefile | 1 +
drivers/misc/xlink-pcie/Kconfig | 9 +
drivers/misc/xlink-pcie/Makefile | 1 +
drivers/misc/xlink-pcie/local_host/Makefile | 2 +
drivers/misc/xlink-pcie/local_host/epf.c | 373 ++++++++++++++++++++
drivers/misc/xlink-pcie/local_host/epf.h | 37 ++
drivers/misc/xlink-pcie/local_host/xpcie.h | 38 ++
9 files changed, 468 insertions(+)
create mode 100644 drivers/misc/xlink-pcie/Kconfig
create mode 100644 drivers/misc/xlink-pcie/Makefile
create mode 100644 drivers/misc/xlink-pcie/local_host/Makefile
create mode 100644 drivers/misc/xlink-pcie/local_host/epf.c
create mode 100644 drivers/misc/xlink-pcie/local_host/epf.h
create mode 100644 drivers/misc/xlink-pcie/local_host/xpcie.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 797a1ff7057c..1154d3e6b359 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1961,6 +1961,12 @@ F: Documentation/devicetree/bindings/arm/intel,keembay.yaml
F: arch/arm64/boot/dts/intel/keembay-evm.dts
F: arch/arm64/boot/dts/intel/keembay-soc.dtsi

+ARM KEEM BAY XLINK PCIE SUPPORT
+M: Srikanth Thokala <srikanth.thokala@intel.com>
+M: Mark Gross <mgross@linux.intel.com>
+S: Supported
+F: drivers/misc/xlink-pcie/
+
ARM/INTEL RESEARCH IMOTE/STARGATE 2 MACHINE SUPPORT
M: Jonathan Cameron <jic23@cam.ac.uk>
L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index fafa8b0d8099..dfb98e444c6e 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -481,4 +481,5 @@ source "drivers/misc/ocxl/Kconfig"
source "drivers/misc/cardreader/Kconfig"
source "drivers/misc/habanalabs/Kconfig"
source "drivers/misc/uacce/Kconfig"
+source "drivers/misc/xlink-pcie/Kconfig"
endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index d23231e73330..d17621fc43d5 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_HABANA_AI) += habanalabs/
obj-$(CONFIG_UACCE) += uacce/
obj-$(CONFIG_XILINX_SDFEC) += xilinx_sdfec.o
obj-$(CONFIG_HISI_HIKEY_USB) += hisi_hikey_usb.o
+obj-y += xlink-pcie/
diff --git a/drivers/misc/xlink-pcie/Kconfig b/drivers/misc/xlink-pcie/Kconfig
new file mode 100644
index 000000000000..46aa401d79b7
--- /dev/null
+++ b/drivers/misc/xlink-pcie/Kconfig
@@ -0,0 +1,9 @@
+config XLINK_PCIE_LH_DRIVER
+ tristate "XLink PCIe Local Host driver"
+ depends on PCI_ENDPOINT && ARCH_KEEMBAY
+ help
+ This option enables XLink PCIe Local Host driver.
+
+ Choose M here to compile this driver as a module, name is mxlk_ep.
+ This driver is used for XLink communication over PCIe and is to be
+ loaded on the Intel Keem Bay platform.
diff --git a/drivers/misc/xlink-pcie/Makefile b/drivers/misc/xlink-pcie/Makefile
new file mode 100644
index 000000000000..d693d382e9c6
--- /dev/null
+++ b/drivers/misc/xlink-pcie/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_XLINK_PCIE_LH_DRIVER) += local_host/
diff --git a/drivers/misc/xlink-pcie/local_host/Makefile b/drivers/misc/xlink-pcie/local_host/Makefile
new file mode 100644
index 000000000000..514d3f0c91bc
--- /dev/null
+++ b/drivers/misc/xlink-pcie/local_host/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_XLINK_PCIE_LH_DRIVER) += mxlk_ep.o
+mxlk_ep-objs := epf.o
diff --git a/drivers/misc/xlink-pcie/local_host/epf.c b/drivers/misc/xlink-pcie/local_host/epf.c
new file mode 100644
index 000000000000..0234756e89ae
--- /dev/null
+++ b/drivers/misc/xlink-pcie/local_host/epf.c
@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Keem Bay XLink PCIe Driver
+ *
+ * Copyright (C) 2021 Intel Corporation
+ */
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#include "epf.h"
+
+#define BAR2_MIN_SIZE SZ_16K
+#define BAR4_MIN_SIZE SZ_16K
+
+#define PCIE_REGS_PCIE_INTR_ENABLE 0x18
+#define PCIE_REGS_PCIE_INTR_FLAGS 0x1C
+#define LBC_CII_EVENT_FLAG BIT(18)
+#define PCIE_REGS_PCIE_ERR_INTR_FLAGS 0x24
+#define LINK_REQ_RST_FLG BIT(15)
+
+static struct pci_epf_header xpcie_header = {
+ .vendorid = PCI_VENDOR_ID_INTEL,
+ .deviceid = PCI_DEVICE_ID_INTEL_KEEMBAY,
+ .baseclass_code = PCI_BASE_CLASS_MULTIMEDIA,
+ .subclass_code = 0x0,
+ .subsys_vendor_id = 0x0,
+ .subsys_id = 0x0,
+};
+
+static const struct pci_epf_device_id xpcie_epf_ids[] = {
+ {
+ .name = "mxlk_pcie_epf",
+ },
+ {},
+};
+
+static irqreturn_t intel_xpcie_err_interrupt(int irq, void *args)
+{
+ struct xpcie_epf *xpcie_epf;
+ struct xpcie *xpcie = args;
+ u32 val;
+
+ xpcie_epf = container_of(xpcie, struct xpcie_epf, xpcie);
+ val = ioread32(xpcie_epf->apb_base + PCIE_REGS_PCIE_ERR_INTR_FLAGS);
+
+ iowrite32(val, xpcie_epf->apb_base + PCIE_REGS_PCIE_ERR_INTR_FLAGS);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t intel_xpcie_host_interrupt(int irq, void *args)
+{
+ struct xpcie_epf *xpcie_epf;
+ struct xpcie *xpcie = args;
+ u32 val;
+
+ xpcie_epf = container_of(xpcie, struct xpcie_epf, xpcie);
+ val = ioread32(xpcie_epf->apb_base + PCIE_REGS_PCIE_INTR_FLAGS);
+ if (val & LBC_CII_EVENT_FLAG) {
+ iowrite32(LBC_CII_EVENT_FLAG,
+ xpcie_epf->apb_base + PCIE_REGS_PCIE_INTR_FLAGS);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void
+intel_xpcie_configure_bar(struct pci_epf *epf,
+ const struct pci_epc_features *epc_features)
+{
+ struct pci_epf_bar *epf_bar;
+ bool bar_fixed_64bit;
+ int i;
+
+ for (i = BAR_0; i <= BAR_5; i++) {
+ epf_bar = &epf->bar[i];
+ bar_fixed_64bit = !!(epc_features->bar_fixed_64bit & (1 << i));
+ if (bar_fixed_64bit)
+ epf_bar->flags |= PCI_BASE_ADDRESS_MEM_TYPE_64;
+ if (epc_features->bar_fixed_size[i])
+ epf_bar->size = epc_features->bar_fixed_size[i];
+ }
+}
+
+static void intel_xpcie_cleanup_bar(struct pci_epf *epf, enum pci_barno barno)
+{
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+ struct pci_epc *epc = epf->epc;
+
+ if (xpcie_epf->vaddr[barno]) {
+ pci_epc_clear_bar(epc, epf->func_no, &epf->bar[barno]);
+ pci_epf_free_space(epf, xpcie_epf->vaddr[barno], barno);
+ xpcie_epf->vaddr[barno] = NULL;
+ }
+}
+
+static void intel_xpcie_cleanup_bars(struct pci_epf *epf)
+{
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+
+ intel_xpcie_cleanup_bar(epf, BAR_2);
+ intel_xpcie_cleanup_bar(epf, BAR_4);
+ xpcie_epf->xpcie.mmio = NULL;
+ xpcie_epf->xpcie.bar4 = NULL;
+}
+
+static int intel_xpcie_setup_bar(struct pci_epf *epf, enum pci_barno barno,
+ size_t min_size, size_t align)
+{
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+ struct pci_epf_bar *bar = &epf->bar[barno];
+ struct pci_epc *epc = epf->epc;
+ void *vaddr;
+ int ret;
+
+ bar->flags |= PCI_BASE_ADDRESS_MEM_TYPE_64;
+ if (!bar->size)
+ bar->size = min_size;
+
+ if (barno == BAR_4)
+ bar->flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
+
+ vaddr = pci_epf_alloc_space(epf, bar->size, barno, align);
+ if (!vaddr) {
+ dev_err(&epf->dev, "Failed to map BAR%d\n", barno);
+ return -ENOMEM;
+ }
+
+ ret = pci_epc_set_bar(epc, epf->func_no, bar);
+ if (ret) {
+ pci_epf_free_space(epf, vaddr, barno);
+ dev_err(&epf->dev, "Failed to set BAR%d\n", barno);
+ return ret;
+ }
+
+ xpcie_epf->vaddr[barno] = vaddr;
+
+ return 0;
+}
+
+static int intel_xpcie_setup_bars(struct pci_epf *epf, size_t align)
+{
+ int ret;
+
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+
+ ret = intel_xpcie_setup_bar(epf, BAR_2, BAR2_MIN_SIZE, align);
+ if (ret)
+ return ret;
+
+ ret = intel_xpcie_setup_bar(epf, BAR_4, BAR4_MIN_SIZE, align);
+ if (ret) {
+ intel_xpcie_cleanup_bar(epf, BAR_2);
+ return ret;
+ }
+
+ xpcie_epf->comm_bar = BAR_2;
+ xpcie_epf->xpcie.mmio = (void *)xpcie_epf->vaddr[BAR_2] +
+ XPCIE_MMIO_OFFSET;
+
+ xpcie_epf->bar4 = BAR_4;
+ xpcie_epf->xpcie.bar4 = xpcie_epf->vaddr[BAR_4];
+
+ return 0;
+}
+
+static int intel_xpcie_epf_get_platform_data(struct device *dev,
+ struct xpcie_epf *xpcie_epf)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct device_node *soc_node, *version_node;
+ struct resource *res;
+ const char *prop;
+ int prop_size;
+
+ xpcie_epf->irq_dma = platform_get_irq_byname(pdev, "intr");
+ if (xpcie_epf->irq_dma < 0) {
+ dev_err(&xpcie_epf->epf->dev, "failed to get IRQ: %d\n",
+ xpcie_epf->irq_dma);
+ return -EINVAL;
+ }
+
+ xpcie_epf->irq_err = platform_get_irq_byname(pdev, "err_intr");
+ if (xpcie_epf->irq_err < 0) {
+ dev_err(&xpcie_epf->epf->dev, "failed to get erroe IRQ: %d\n",
+ xpcie_epf->irq_err);
+ return -EINVAL;
+ }
+
+ xpcie_epf->irq = platform_get_irq_byname(pdev, "ev_intr");
+ if (xpcie_epf->irq < 0) {
+ dev_err(&xpcie_epf->epf->dev, "failed to get event IRQ: %d\n",
+ xpcie_epf->irq);
+ return -EINVAL;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb");
+ xpcie_epf->apb_base =
+ devm_ioremap(dev, res->start, resource_size(res));
+ if (IS_ERR(xpcie_epf->apb_base))
+ return PTR_ERR(xpcie_epf->apb_base);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ xpcie_epf->dbi_base =
+ devm_ioremap(dev, res->start, resource_size(res));
+ if (IS_ERR(xpcie_epf->dbi_base))
+ return PTR_ERR(xpcie_epf->dbi_base);
+
+ memcpy(xpcie_epf->stepping, "B0", 2);
+ soc_node = of_get_parent(pdev->dev.of_node);
+ if (soc_node) {
+ version_node = of_get_child_by_name(soc_node, "version-info");
+ if (version_node) {
+ prop = of_get_property(version_node, "stepping",
+ &prop_size);
+ if (prop && prop_size <= KEEMBAY_XPCIE_STEPPING_MAXLEN)
+ memcpy(xpcie_epf->stepping, prop, prop_size);
+ of_node_put(version_node);
+ }
+ of_node_put(soc_node);
+ }
+
+ return 0;
+}
+
+static int intel_xpcie_epf_bind(struct pci_epf *epf)
+{
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+ const struct pci_epc_features *features;
+ struct pci_epc *epc = epf->epc;
+ struct device *dev;
+ size_t align = SZ_16K;
+ int ret;
+
+ if (WARN_ON_ONCE(!epc))
+ return -EINVAL;
+
+ dev = epc->dev.parent;
+ features = pci_epc_get_features(epc, epf->func_no);
+ xpcie_epf->epc_features = features;
+ if (features) {
+ align = features->align;
+ intel_xpcie_configure_bar(epf, features);
+ }
+
+ ret = intel_xpcie_setup_bars(epf, align);
+ if (ret) {
+ dev_err(&epf->dev, "BAR initialization failed\n");
+ return ret;
+ }
+
+ ret = intel_xpcie_epf_get_platform_data(dev, xpcie_epf);
+ if (ret) {
+ dev_err(&epf->dev, "Unable to get platform data\n");
+ return -EINVAL;
+ }
+
+ if (!strcmp(xpcie_epf->stepping, "A0")) {
+ xpcie_epf->xpcie.legacy_a0 = true;
+ iowrite32(1, (void __iomem *)xpcie_epf->xpcie.mmio +
+ XPCIE_MMIO_LEGACY_A0);
+ } else {
+ xpcie_epf->xpcie.legacy_a0 = false;
+ iowrite32(0, (void __iomem *)xpcie_epf->xpcie.mmio +
+ XPCIE_MMIO_LEGACY_A0);
+ }
+
+ /* Enable interrupt */
+ writel(LBC_CII_EVENT_FLAG,
+ xpcie_epf->apb_base + PCIE_REGS_PCIE_INTR_ENABLE);
+ ret = devm_request_irq(&epf->dev, xpcie_epf->irq,
+ &intel_xpcie_host_interrupt, 0,
+ XPCIE_DRIVER_NAME, &xpcie_epf->xpcie);
+ if (ret) {
+ dev_err(&epf->dev, "failed to request irq\n");
+ goto err_cleanup_bars;
+ }
+
+ ret = devm_request_irq(&epf->dev, xpcie_epf->irq_err,
+ &intel_xpcie_err_interrupt, 0,
+ XPCIE_DRIVER_NAME, &xpcie_epf->xpcie);
+ if (ret) {
+ dev_err(&epf->dev, "failed to request error irq\n");
+ goto err_cleanup_bars;
+ }
+
+ return 0;
+
+err_cleanup_bars:
+ intel_xpcie_cleanup_bars(epf);
+
+ return ret;
+}
+
+static void intel_xpcie_epf_unbind(struct pci_epf *epf)
+{
+ struct xpcie_epf *xpcie_epf = epf_get_drvdata(epf);
+ struct pci_epc *epc = epf->epc;
+
+ free_irq(xpcie_epf->irq, &xpcie_epf->xpcie);
+ free_irq(xpcie_epf->irq_err, &xpcie_epf->xpcie);
+
+ pci_epc_stop(epc);
+
+ intel_xpcie_cleanup_bars(epf);
+}
+
+static int intel_xpcie_epf_probe(struct pci_epf *epf)
+{
+ struct device *dev = &epf->dev;
+ struct xpcie_epf *xpcie_epf;
+
+ xpcie_epf = devm_kzalloc(dev, sizeof(*xpcie_epf), GFP_KERNEL);
+ if (!xpcie_epf)
+ return -ENOMEM;
+
+ epf->header = &xpcie_header;
+ xpcie_epf->epf = epf;
+ epf_set_drvdata(epf, xpcie_epf);
+
+ return 0;
+}
+
+static void intel_xpcie_epf_shutdown(struct device *dev)
+{
+ struct pci_epf *epf = to_pci_epf(dev);
+ struct xpcie_epf *xpcie_epf;
+
+ xpcie_epf = epf_get_drvdata(epf);
+
+ /* Notify host in case PCIe hot plug not supported */
+ if (xpcie_epf)
+ pci_epc_raise_irq(epf->epc, epf->func_no, PCI_EPC_IRQ_MSI, 1);
+}
+
+static struct pci_epf_ops ops = {
+ .bind = intel_xpcie_epf_bind,
+ .unbind = intel_xpcie_epf_unbind,
+};
+
+static struct pci_epf_driver xpcie_epf_driver = {
+ .driver.name = "mxlk_pcie_epf",
+ .driver.shutdown = intel_xpcie_epf_shutdown,
+ .probe = intel_xpcie_epf_probe,
+ .id_table = xpcie_epf_ids,
+ .ops = &ops,
+ .owner = THIS_MODULE,
+};
+
+static int __init intel_xpcie_epf_init(void)
+{
+ int ret;
+
+ ret = pci_epf_register_driver(&xpcie_epf_driver);
+ if (ret) {
+ pr_err("Failed to register xlink pcie epf driver: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+module_init(intel_xpcie_epf_init);
+
+static void __exit intel_xpcie_epf_exit(void)
+{
+ pci_epf_unregister_driver(&xpcie_epf_driver);
+}
+module_exit(intel_xpcie_epf_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION(XPCIE_DRIVER_DESC);
diff --git a/drivers/misc/xlink-pcie/local_host/epf.h b/drivers/misc/xlink-pcie/local_host/epf.h
new file mode 100644
index 000000000000..a60cd43fe555
--- /dev/null
+++ b/drivers/misc/xlink-pcie/local_host/epf.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Intel Keem Bay XLink PCIe Driver
+ *
+ * Copyright (C) 2021 Intel Corporation
+ */
+
+#ifndef XPCIE_EPF_HEADER_
+#define XPCIE_EPF_HEADER_
+
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+
+#include "xpcie.h"
+
+#define XPCIE_DRIVER_NAME "mxlk_pcie_epf"
+#define XPCIE_DRIVER_DESC "Intel(R) xLink PCIe endpoint function driver"
+
+#define KEEMBAY_XPCIE_STEPPING_MAXLEN 8
+
+struct xpcie_epf {
+ struct pci_epf *epf;
+ void *vaddr[BAR_5 + 1];
+ enum pci_barno comm_bar;
+ enum pci_barno bar4;
+ const struct pci_epc_features *epc_features;
+ struct xpcie xpcie;
+ int irq;
+ int irq_dma;
+ int irq_err;
+ void __iomem *apb_base;
+ void __iomem *dma_base;
+ void __iomem *dbi_base;
+ char stepping[KEEMBAY_XPCIE_STEPPING_MAXLEN];
+};
+
+#endif /* XPCIE_EPF_HEADER_ */
diff --git a/drivers/misc/xlink-pcie/local_host/xpcie.h b/drivers/misc/xlink-pcie/local_host/xpcie.h
new file mode 100644
index 000000000000..0745e6dfee10
--- /dev/null
+++ b/drivers/misc/xlink-pcie/local_host/xpcie.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*****************************************************************************
+ *
+ * Intel Keem Bay XLink PCIe Driver
+ *
+ * Copyright (C) 2020 Intel Corporation
+ *
+ ****************************************************************************/
+
+#ifndef XPCIE_HEADER_
+#define XPCIE_HEADER_
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci_ids.h>
+
+#ifndef PCI_DEVICE_ID_INTEL_KEEMBAY
+#define PCI_DEVICE_ID_INTEL_KEEMBAY 0x6240
+#endif
+
+#define XPCIE_IO_COMM_SIZE SZ_16K
+#define XPCIE_MMIO_OFFSET SZ_4K
+
+/* MMIO layout and offsets shared between device and host */
+struct xpcie_mmio {
+ u8 legacy_a0;
+} __packed;
+
+#define XPCIE_MMIO_LEGACY_A0 (offsetof(struct xpcie_mmio, legacy_a0))
+
+struct xpcie {
+ u32 status;
+ bool legacy_a0;
+ void *mmio;
+ void *bar4;
+};
+
+#endif /* XPCIE_HEADER_ */
--
2.17.1