pci_ep: add pci endpoint sandbox driver

Add a dummy PCI endpoint for sandbox.
Supporting only a single function, it allows setting
and reading header configuration.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/Kconfig

@@ -90,6 +90,7 @@ config SANDBOX
 	select DM_SPI_FLASH
 	select HAVE_BLOCK_DEVICE
 	select LZO
+	select PCI_ENDPOINT
 	select SPI
 	select SUPPORT_OF_CONTROL
 	imply BITREVERSE
@@ -120,6 +121,7 @@ config SANDBOX
 	imply VIRTIO_BLK
 	imply VIRTIO_NET
 	imply DM_SOUND
+	imply PCI_SANDBOX_EP
 	imply PCH
 
 config SH

arch/sandbox/dts/test.dts

@@ -487,6 +487,10 @@
 		};
 	};
 
+	pci_ep: pci_ep {
+		compatible = "sandbox,pci_ep";
+	};
+
 	probing {
 		compatible = "simple-bus";
 		test1 {

drivers/pci_endpoint/Kconfig

@@ -22,4 +22,13 @@ config PCIE_CADENCE_EP
 	  endpoint mode. This PCIe controller may be embedded into many
 	  different vendors SoCs.
 
+config PCI_SANDBOX_EP
+	bool "Sandbox PCIe endpoint controller"
+	depends on PCI_ENDPOINT
+	help
+	  Say Y here if you want to support the Sandbox PCIe controller in
+	  endpoint mode.
+	  The sandbox driver act as a dummy driver which stores and
+	  retrieves PCIe endpoint configuration as is.
+
 endmenu

drivers/pci_endpoint/Makefile

@@ -5,3 +5,4 @@
 
 obj-y += pci_ep-uclass.o
 obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o
+obj-$(CONFIG_PCI_SANDBOX_EP) += sandbox-pci_ep.o

drivers/pci_endpoint/sandbox-pci_ep.c

@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2019 Ramon Fried <ramon.fried@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <pci.h>
+#include <pci_ep.h>
+#include <asm/test.h>
+
+/**
+ * struct sandbox_pci_ep_priv - private data for driver
+ * @hdr: Stores the EP device header
+ * @msix: required MSIx count;
+ * @msi: required MSI count;
+ */
+struct sandbox_pci_ep_priv {
+	struct pci_ep_header hdr;
+	struct pci_bar bars[6];
+	int msix;
+	int msi;
+	int irq_count;
+};
+
+/* Method exported for testing purposes */
+int sandbox_get_pci_ep_irq_count(struct udevice *dev)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	return priv->irq_count;
+}
+
+static const struct udevice_id sandbox_pci_ep_ids[] = {
+	{ .compatible = "sandbox,pci_ep" },
+	{ }
+};
+
+static int sandbox_write_header(struct udevice *dev, uint fn,
+				struct pci_ep_header *hdr)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	memcpy(&priv->hdr, hdr, sizeof(*hdr));
+
+	return 0;
+}
+
+static int sandbox_read_header(struct udevice *dev, uint fn,
+			       struct pci_ep_header *hdr)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	memcpy(hdr, &priv->hdr, sizeof(*hdr));
+
+	return 0;
+}
+
+static int sandbox_set_bar(struct udevice *dev, uint fn,
+			   struct pci_bar *ep_bar)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+	int bar_idx;
+
+	if (fn > 0)
+		return -ENODEV;
+
+	bar_idx = ep_bar->barno;
+
+	memcpy(&priv->bars[bar_idx], ep_bar, sizeof(*ep_bar));
+
+	return 0;
+}
+
+static int sandbox_read_bar(struct udevice *dev, uint fn,
+			    struct pci_bar *ep_bar, enum pci_barno barno)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+	int bar_idx;
+
+	if (fn > 0)
+		return -ENODEV;
+
+	bar_idx = ep_bar->barno;
+
+	memcpy(ep_bar, &priv->bars[bar_idx], sizeof(*ep_bar));
+
+	return 0;
+}
+
+static int sandbox_set_msi(struct udevice *dev, uint fn, uint interrupts)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	priv->msi = interrupts;
+
+	return 0;
+}
+
+static int sandbox_get_msi(struct udevice *dev, uint fn)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	return priv->msi;
+}
+
+static int sandbox_set_msix(struct udevice *dev, uint fn, uint interrupts)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	priv->msix = interrupts;
+
+	return 0;
+}
+
+static int sandbox_get_msix(struct udevice *dev, uint fn)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	return priv->msix;
+}
+
+static int sandbox_raise_irq(struct udevice *dev, uint fn,
+			     enum pci_ep_irq_type type, uint interrupt_num)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	if (fn > 0)
+		return -ENODEV;
+
+	priv->irq_count++;
+
+	return 0;
+}
+
+static int sandbox_pci_ep_probe(struct udevice *dev)
+{
+	struct sandbox_pci_ep_priv *priv = dev_get_priv(dev);
+
+	memset(priv, 0, sizeof(*priv));
+	return 0;
+}
+
+static struct pci_ep_ops sandbox_pci_ep_ops = {
+	.write_header = sandbox_write_header,
+	.read_header = sandbox_read_header,
+	.set_bar = sandbox_set_bar,
+	.read_bar = sandbox_read_bar,
+	.set_msi = sandbox_set_msi,
+	.get_msi = sandbox_get_msi,
+	.set_msix = sandbox_set_msix,
+	.get_msix = sandbox_get_msix,
+	.raise_irq = sandbox_raise_irq,
+};
+
+U_BOOT_DRIVER(pci_ep_sandbox) = {
+	.name		= "pci_ep_sandbox",
+	.id		= UCLASS_PCI_EP,
+	.of_match	= sandbox_pci_ep_ids,
+	.probe		= sandbox_pci_ep_probe,
+	.ops		= &sandbox_pci_ep_ops,
+	.priv_auto_alloc_size = sizeof(struct sandbox_pci_ep_priv),
+};