Commit 3229b906 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

lib: devres: Add managed arch_phys_wc_add() 



Add devm_arch_phys_wc_add() as managed wrapper around arch_phys_wc_add().
Useful for several graphics drivers that set framebuffer memory to write
combining.

v2:
	* fix typo in commit description

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916181601.9146-2-tzimmermann@suse.de
parent 9c2fce13

include/linux/io.h

+2 −0
Original line number Diff line number Diff line
@@ -132,6 +132,8 @@ static inline int arch_phys_wc_index(int handle) 
#endif

#endif



int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size);



enum {

	/* See memremap() kernel-doc for usage description... */

	MEMREMAP_WB = 1 << 0,

lib/devres.c

+36 −0
Original line number Diff line number Diff line
@@ -528,3 +528,39 @@ void pcim_iounmap_regions(struct pci_dev *pdev, int mask) 
}

EXPORT_SYMBOL(pcim_iounmap_regions);

#endif /* CONFIG_PCI */



static void devm_arch_phys_ac_add_release(struct device *dev, void *res)

{

	arch_phys_wc_del(*((int *)res));

}



/**

 * devm_arch_phys_wc_add - Managed arch_phys_wc_add()

 * @dev: Managed device

 * @base: Memory base address

 * @size: Size of memory range

 *

 * Adds a WC MTRR using arch_phys_wc_add() and sets up a release callback.

 * See arch_phys_wc_add() for more information.

 */

int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size)

{

	int *mtrr;

	int ret;



	mtrr = devres_alloc(devm_arch_phys_ac_add_release, sizeof(*mtrr), GFP_KERNEL);

	if (!mtrr)

		return -ENOMEM;



	ret = arch_phys_wc_add(base, size);

	if (ret < 0) {

		devres_free(mtrr);

		return ret;

	}



	*mtrr = ret;

	devres_add(dev, mtrr);



	return ret;

}

EXPORT_SYMBOL(devm_arch_phys_wc_add);