Re: [RFC PATCH 1/3] pci: APM X-Gene PCIe controller driver

[Jingoo Han <jg1.han@samsung.com>]

On Monday, December 23, 2013 5:02 PM, Tanmay Inamdar wrote:
> 
> This patch adds the AppliedMicro X-gene SOC PCIe controller driver.
> APM X-Gene PCIe controller supports maximum upto 8 lanes and
> GEN3 speed. X-Gene has maximum 5 PCIe ports supported.

(+cc Jason Gunthorpe, Arnd Bergmann)

Hi Tanmay Inamdar,

I added some minor comments. :-)

> 
> Signed-off-by: Tanmay Inamdar <tinamdar@apm.com>
> ---
>  drivers/pci/host/Kconfig      |    5 +
>  drivers/pci/host/Makefile     |    1 +
>  drivers/pci/host/pcie-xgene.c | 1017 +++++++++++++++++++++++++++++++++++++++++

Would you change the file name to 'pci-xgene.c'?
Now, all PCI host drivers are using the prefix 'pci-', not 'pcie-'.

[.....]

> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/pci.h>
> +#include <linux/slab.h>
> +#include <linux/memblock.h>
> +#include <linux/io.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_pci.h>
> +#include <linux/jiffies.h>
> +#include <linux/clk-private.h>

Would you re-order these headers alphabetically?
It enhances the readability.

[.....]

> +static int xgene_pcie_parse_map_ranges(struct xgene_pcie_port *port)
> +{
> +	struct device_node *np = port->node;
> +	struct of_pci_range range;
> +	struct of_pci_range_parser parser;
> +	struct device *dev = port->dev;
> +	u32 cfg_map_done = 0;
> +	int ret;
> +
> +	if (of_pci_range_parser_init(&parser, np)) {
> +		dev_err(dev, "missing ranges property\n");
> +		return -EINVAL;
> +	}
> +
> +	/* Get the I/O, memory, config ranges from DT */
> +	for_each_of_pci_range(&parser, &range) {
> +		struct resource *res = NULL;
> +		u64 restype = range.flags & IORESOURCE_TYPE_BITS;
> +		u64 end = range.cpu_addr + range.size - 1;
> +		dev_dbg(port->dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n",
> +			range.flags, range.cpu_addr, end, range.pci_addr);
> +
> +		switch (restype) {
> +		case IORESOURCE_IO:
> +			res = &port->res[XGENE_IO];
> +			of_pci_range_to_resource(&range, np, res);
> +			xgene_pcie_setup_ob_reg(port->csr_base, OMR1BARL,
> +						XGENE_IO, res);
> +			break;
> +		case IORESOURCE_MEM:
> +			res = &port->res[XGENE_MEM];
> +			of_pci_range_to_resource(&range, np, res);
> +			xgene_pcie_setup_ob_reg(port->csr_base, OMR2BARL,
> +						XGENE_MEM, res);
> +			break;
> +		case 0:
> +			if (!cfg_map_done) {
> +				/* config region */
> +				if (port->type == PTYPE_ROOT_PORT) {
> +					ret = xgene_pcie_map_cfg(port, &range);
> +					if (ret)
> +						return ret;
> +				}
> +				cfg_map_done = 1;
> +			} else {
> +				/* msi region */
> +				res = &port->res[XGENE_MSI];
> +				of_pci_range_to_resource(&range, np, res);

As Jason Gunthorpe said, the DT 'range' property should not
handle MSI. Please refer to other PCI host drivers such as
pci-mvebu.c, pci-tegra.c and pcie-designware.c.

Currently, 'struct msi_chip', ' struct irq_domain' are used 
for implementing MSI feature.

Best regards,
Jingoo Han