Re: [PATCH V5 2/3] PCI: Create device tree node for selected devices

[Clément Léger]

Le Thu, 15 Dec 2022 09:30:45 -0800,
Lizhi Hou <lizhi.hou@xxxxxxx> a écrit :

Further comments

> diff --git a/drivers/pci/of_property.c b/drivers/pci/of_property.c
> new file mode 100644
> index 000000000000..05c8ca05a71b
> --- /dev/null
> +++ b/drivers/pci/of_property.c
> @@ -0,0 +1,222 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2022, Advanced Micro Devices, Inc.
> + */
> +
> +#include <linux/pci.h>
> +#include <linux/of.h>
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <asm/unaligned.h>
> +#include "pci.h"
> +
> +#define OF_PCI_ADDRESS_CELLS		3
> +#define OF_PCI_SIZE_CELLS		2
> +
> +struct of_pci_addr_pair {
> +	u32		phys_addr[OF_PCI_ADDRESS_CELLS];
> +	u32		size[OF_PCI_SIZE_CELLS];
> +};
> +
> +struct of_pci_range {
> +	u32		child_addr[OF_PCI_ADDRESS_CELLS];
> +	u32		parent_addr[OF_PCI_ADDRESS_CELLS];
> +	u32		size[OF_PCI_SIZE_CELLS];
> +};
> +
> +#define OF_PCI_ADDR_SPACE_CONFIG	0x0
> +#define OF_PCI_ADDR_SPACE_IO		0x1
> +#define OF_PCI_ADDR_SPACE_MEM32		0x2
> +#define OF_PCI_ADDR_SPACE_MEM64		0x3
> +
> +#define OF_PCI_ADDR_FIELD_NONRELOC	BIT(31)
> +#define OF_PCI_ADDR_FIELD_SS		GENMASK(25, 24)
> +#define OF_PCI_ADDR_FIELD_PREFETCH	BIT(30)
> +#define OF_PCI_ADDR_FIELD_BUS		GENMASK(23, 16)
> +#define OF_PCI_ADDR_FIELD_DEV		GENMASK(15, 11)
> +#define OF_PCI_ADDR_FIELD_FUNC		GENMASK(10, 8)
> +#define OF_PCI_ADDR_FIELD_REG		GENMASK(7, 0)
> +
> +#define OF_PCI_ADDR_HI			GENMASK_ULL(63, 32)
> +#define OF_PCI_ADDR_LO			GENMASK_ULL(31, 0)
> +#define OF_PCI_SIZE_HI			GENMASK_ULL(63, 32)
> +#define OF_PCI_SIZE_LO			GENMASK_ULL(31, 0)

This is unused.

> +
> +enum of_pci_prop_compatible {
> +	PROP_COMPAT_PCI_VVVV_DDDD,
> +	PROP_COMPAT_PCICLASS_CCSSPP,
> +	PROP_COMPAT_PCICLASS_CCSS,
> +	PROP_COMPAT_NUM,
> +};
> +
> +static int of_pci_prop_device_type(struct pci_dev *pdev,
> +				   struct of_changeset *ocs,
> +				   struct device_node *np)
> +{
> +	return of_changeset_add_prop_string(ocs, np, "device_type", "pci");
> +}
> +
> +static int of_pci_prop_address_cells(struct pci_dev *pdev,
> +				     struct of_changeset *ocs,
> +				     struct device_node *np)
> +{
> +	return of_changeset_add_prop_u32(ocs, np, "#address_cells",
> +					 OF_PCI_ADDRESS_CELLS);
> +}
> +
> +static int of_pci_prop_size_cells(struct pci_dev *pdev,
> +				  struct of_changeset *ocs,
> +				  struct device_node *np)
> +{
> +	return of_changeset_add_prop_u32(ocs, np, "#size_cells",
> +					 OF_PCI_SIZE_CELLS);
> +}
> +
> +static void of_pci_set_address(u32 *prop, u64 addr, u32 flags)
> +{
> +	prop[0] = flags;
> +	put_unaligned(addr, &prop[1]);
> +}
> +
> +static int of_pci_get_addr_flags(struct resource *res, u32 *flags)
> +{
> +	u32 ss;
> +
> +	if (res->flags & IORESOURCE_IO)
> +		ss = OF_PCI_ADDR_SPACE_IO;
> +	else if (res->flags & IORESOURCE_MEM_64)
> +		ss = OF_PCI_ADDR_SPACE_MEM64;
> +	else if (res->flags & IORESOURCE_MEM)
> +		ss = OF_PCI_ADDR_SPACE_MEM32;
> +	else
> +		return -EINVAL;
> +
> +	*flags &= ~(OF_PCI_ADDR_FIELD_SS | OF_PCI_ADDR_FIELD_PREFETCH);
> +	if (res->flags & IORESOURCE_PREFETCH)
> +		*flags |= OF_PCI_ADDR_FIELD_PREFETCH;
> +
> +	*flags |= ss;

This seems wrong, should be:

*flags |= FIELD_PREP(OF_PCI_ADDR_FIELD_SS, ss);

-- 
Clément Léger,
Embedded Linux and Kernel engineer at Bootlin
https://bootlin.com