QEMU emulates such a device with '-machine virt,highmem=off' on ARM.
The 'highmem=off' part is required for things to work as the PCI code
in U-Boot doesn't seem to support 64-bit BARs.

This driver is basically a copy-paste of the Xilinx PCIE driver with the
Xilinx-specific bits removed and compatible string changed... The
generic code should probably be extracted into some sort of library
functions instead of duplicating them before committing this driver.

Signed-off-by: Tuomas Tynkkynen <tuomas.tynkky...@iki.fi>
---
 drivers/pci/Kconfig             |   8 ++
 drivers/pci/Makefile            |   1 +
 drivers/pci/pcie_ecam_generic.c | 193 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 202 insertions(+)
 create mode 100644 drivers/pci/pcie_ecam_generic.c

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index e2a1c0a409..745161fb9f 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -33,6 +33,14 @@ config PCI_PNP
        help
          Enable PCI memory and I/O space resource allocation and assignment.
 
+config PCIE_ECAM_GENERIC
+       bool "Generic PCI-E ECAM support"
+       default n
+       depends on DM_PCI
+       help
+         Say Y here if you want to enable support for generic ECAM-based
+         PCIe controllers, such as the one emulated by QEMU.
+
 config PCIE_DW_MVEBU
        bool "Enable Armada-8K PCIe driver (DesignWare core)"
        default n
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index ad44e83996..5eb12efbf5 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_PCI) += pci.o pci_auto_old.o
 endif
 obj-$(CONFIG_PCI) += pci_auto_common.o pci_common.o
 
+obj-$(CONFIG_PCIE_ECAM_GENERIC) += pcie_ecam_generic.o
 obj-$(CONFIG_FSL_PCI_INIT) += fsl_pci_init.o
 obj-$(CONFIG_PCI_INDIRECT_BRIDGE) += pci_indirect.o
 obj-$(CONFIG_PCI_GT64120) += pci_gt64120.o
diff --git a/drivers/pci/pcie_ecam_generic.c b/drivers/pci/pcie_ecam_generic.c
new file mode 100644
index 0000000000..039e378cb0
--- /dev/null
+++ b/drivers/pci/pcie_ecam_generic.c
@@ -0,0 +1,193 @@
+/*
+ * Generic PCIE host provided by e.g. QEMU
+ *
+ * Heavily based on drivers/pci/pcie_xilinx.c
+ *
+ * Copyright (C) 2016 Imagination Technologies
+ *
+ * SPDX-License-Identifier:    GPL-2.0
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <pci.h>
+
+#include <asm/io.h>
+
+/**
+ * struct generic_ecam_pcie - generic_ecam PCIe controller state
+ * @hose: The parent classes PCI controller state
+ * @cfg_base: The base address of memory mapped configuration space
+ */
+struct generic_ecam_pcie {
+       struct pci_controller hose;
+       void *cfg_base;
+};
+
+/**
+ * pcie_generic_ecam_config_address() - Calculate the address of a config 
access
+ * @pcie: Pointer to the PCI controller state
+ * @bdf: Identifies the PCIe device to access
+ * @offset: The offset into the device's configuration space
+ * @paddress: Pointer to the pointer to write the calculates address to
+ *
+ * Calculates the address that should be accessed to perform a PCIe
+ * configuration space access for a given device identified by the PCIe
+ * controller device @pcie and the bus, device & function numbers in @bdf. If
+ * access to the device is not valid then the function will return an error
+ * code. Otherwise the address to access will be written to the pointer pointed
+ * to by @paddress.
+ *
+ * Return: 0 on success, else -ENODEV
+ */
+static int pcie_generic_ecam_config_address(struct generic_ecam_pcie *pcie, 
pci_dev_t bdf,
+                                     uint offset, void **paddress)
+{
+       unsigned int bus = PCI_BUS(bdf);
+       unsigned int dev = PCI_DEV(bdf);
+       unsigned int func = PCI_FUNC(bdf);
+       void *addr;
+
+       addr = pcie->cfg_base;
+       addr += bus << 20;
+       addr += dev << 15;
+       addr += func << 12;
+       addr += offset;
+       *paddress = addr;
+
+       return 0;
+}
+
+/**
+ * pcie_generic_ecam_read_config() - Read from configuration space
+ * @pcie: Pointer to the PCI controller state
+ * @bdf: Identifies the PCIe device to access
+ * @offset: The offset into the device's configuration space
+ * @valuep: A pointer at which to store the read value
+ * @size: Indicates the size of access to perform
+ *
+ * Read a value of size @size from offset @offset within the configuration
+ * space of the device identified by the bus, device & function numbers in @bdf
+ * on the PCI bus @bus.
+ *
+ * Return: 0 on success, else -ENODEV or -EINVAL
+ */
+static int pcie_generic_ecam_read_config(struct udevice *bus, pci_dev_t bdf,
+                                  uint offset, ulong *valuep,
+                                  enum pci_size_t size)
+{
+       struct generic_ecam_pcie *pcie = dev_get_priv(bus);
+       void *address;
+       int err;
+
+       err = pcie_generic_ecam_config_address(pcie, bdf, offset, &address);
+       if (err < 0) {
+               *valuep = pci_get_ff(size);
+               return 0;
+       }
+
+       switch (size) {
+       case PCI_SIZE_8:
+               *valuep = __raw_readb(address);
+               return 0;
+       case PCI_SIZE_16:
+               *valuep = __raw_readw(address);
+               return 0;
+       case PCI_SIZE_32:
+               *valuep = __raw_readl(address);
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+/**
+ * pcie_generic_ecam_write_config() - Write to configuration space
+ * @pcie: Pointer to the PCI controller state
+ * @bdf: Identifies the PCIe device to access
+ * @offset: The offset into the device's configuration space
+ * @value: The value to write
+ * @size: Indicates the size of access to perform
+ *
+ * Write the value @value of size @size from offset @offset within the
+ * configuration space of the device identified by the bus, device & function
+ * numbers in @bdf on the PCI bus @bus.
+ *
+ * Return: 0 on success, else -ENODEV or -EINVAL
+ */
+static int pcie_generic_ecam_write_config(struct udevice *bus, pci_dev_t bdf,
+                                   uint offset, ulong value,
+                                   enum pci_size_t size)
+{
+       struct generic_ecam_pcie *pcie = dev_get_priv(bus);
+       void *address;
+       int err;
+
+       err = pcie_generic_ecam_config_address(pcie, bdf, offset, &address);
+       if (err < 0)
+               return 0;
+
+       switch (size) {
+       case PCI_SIZE_8:
+               __raw_writeb(value, address);
+               return 0;
+       case PCI_SIZE_16:
+               __raw_writew(value, address);
+               return 0;
+       case PCI_SIZE_32:
+               __raw_writel(value, address);
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+/**
+ * pcie_generic_ecam_ofdata_to_platdata() - Translate from DT to device state
+ * @dev: A pointer to the device being operated on
+ *
+ * Translate relevant data from the device tree pertaining to device @dev into
+ * state that the driver will later make use of. This state is stored in the
+ * device's private data structure.
+ *
+ * Return: 0 on success, else -EINVAL
+ */
+static int pcie_generic_ecam_ofdata_to_platdata(struct udevice *dev)
+{
+       struct generic_ecam_pcie *pcie = dev_get_priv(dev);
+       struct fdt_resource reg_res;
+       DECLARE_GLOBAL_DATA_PTR;
+       int err;
+
+       err = fdt_get_resource(gd->fdt_blob, dev_of_offset(dev), "reg",
+                              0, &reg_res);
+       if (err < 0) {
+               error("\"reg\" resource not found\n");
+               return err;
+       }
+
+       pcie->cfg_base = map_physmem(reg_res.start,
+                                    fdt_resource_size(&reg_res),
+                                    MAP_NOCACHE);
+
+       return 0;
+}
+
+static const struct dm_pci_ops pcie_generic_ecam_ops = {
+       .read_config    = pcie_generic_ecam_read_config,
+       .write_config   = pcie_generic_ecam_write_config,
+};
+
+static const struct udevice_id pcie_generic_ecam_ids[] = {
+       { .compatible = "pci-host-ecam-generic" },
+       { }
+};
+
+U_BOOT_DRIVER(pcie_generic_ecam) = {
+       .name                   = "pcie_generic_ecam",
+       .id                     = UCLASS_PCI,
+       .of_match               = pcie_generic_ecam_ids,
+       .ops                    = &pcie_generic_ecam_ops,
+       .ofdata_to_platdata     = pcie_generic_ecam_ofdata_to_platdata,
+       .priv_auto_alloc_size   = sizeof(struct generic_ecam_pcie),
+};
-- 
2.13.0

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