Commit b0310c2f authored by Laurentiu Tudor's avatar Laurentiu Tudor Committed by Christoph Hellwig
Browse files

USB: use genalloc for USB HCs with local memory 



For HCs that have local memory, replace the current DMA API usage with
a genalloc generic allocator to manage the mappings for these devices.
To help users, introduce a new HCD API, usb_hcd_setup_local_mem() that
will setup up the genalloc backing up the device local memory. It will
be used in subsequent patches.  This is in preparation for dropping
the existing "coherent" dma mem declaration APIs.  The current
implementation was relying on a short circuit in the DMA API that in
the end, was acting as an allocator for these type of devices.

Signed-off-by: default avatarLaurentiu Tudor <laurentiu.tudor@nxp.com>
Tested-by: default avatarFredrik Noring <noring@nocrew.org>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent da83a722

drivers/usb/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -45,6 +45,7 @@ config USB_ARCH_HAS_HCD 
config USB

	tristate "Support for Host-side USB"

	depends on USB_ARCH_HAS_HCD

	select GENERIC_ALLOCATOR

	select USB_COMMON

	select NLS  # for UTF-8 strings

	---help---

drivers/usb/core/buffer.c

+9 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/io.h>

#include <linux/dma-mapping.h>

#include <linux/dmapool.h>

#include <linux/genalloc.h>

#include <linux/usb.h>

#include <linux/usb/hcd.h>
@@ -124,6 +125,9 @@ void *hcd_buffer_alloc( 
	if (size == 0)

		return NULL;



	if (hcd->localmem_pool)

		return gen_pool_dma_alloc(hcd->localmem_pool, size, dma);



	/* some USB hosts just use PIO */

	if (!IS_ENABLED(CONFIG_HAS_DMA) ||

	    (!is_device_dma_capable(bus->sysdev) &&
@@ -152,6 +156,11 @@ void hcd_buffer_free( 
	if (!addr)

		return;



	if (hcd->localmem_pool) {

		gen_pool_free(hcd->localmem_pool, (unsigned long)addr, size);

		return;

	}



	if (!IS_ENABLED(CONFIG_HAS_DMA) ||

	    (!is_device_dma_capable(bus->sysdev) &&

	     !(hcd->driver->flags & HCD_LOCAL_MEM))) {

drivers/usb/core/hcd.c

+36 −0
Original line number Diff line number Diff line
@@ -29,6 +29,8 @@ 
#include <linux/workqueue.h>

#include <linux/pm_runtime.h>

#include <linux/types.h>

#include <linux/genalloc.h>

#include <linux/io.h>



#include <linux/phy/phy.h>

#include <linux/usb.h>
@@ -3039,6 +3041,40 @@ usb_hcd_platform_shutdown(struct platform_device *dev) 
}

EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);



int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,

			    dma_addr_t dma, size_t size)

{

	int err;

	void *local_mem;



	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, PAGE_SHIFT,

						  dev_to_node(hcd->self.sysdev),

						  dev_name(hcd->self.sysdev));

	if (IS_ERR(hcd->localmem_pool))

		return PTR_ERR(hcd->localmem_pool);



	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,

				  size, MEMREMAP_WC);

	if (!local_mem)

		return -ENOMEM;



	/*

	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.

	 * It's not backed by system memory and thus there's no kernel mapping

	 * for it.

	 */

	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,

				dma, size, dev_to_node(hcd->self.sysdev));

	if (err < 0) {

		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",

			err);

		return err;

	}



	return 0;

}

EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);



/*-------------------------------------------------------------------------*/



#if IS_ENABLED(CONFIG_USB_MON)

drivers/usb/host/ohci-hcd.c

+18 −5
Original line number Diff line number Diff line
@@ -40,6 +40,7 @@ 
#include <linux/dmapool.h>

#include <linux/workqueue.h>

#include <linux/debugfs.h>

#include <linux/genalloc.h>



#include <asm/io.h>

#include <asm/irq.h>
@@ -505,8 +506,15 @@ static int ohci_init (struct ohci_hcd *ohci) 
	timer_setup(&ohci->io_watchdog, io_watchdog_func, 0);

	ohci->prev_frame_no = IO_WATCHDOG_OFF;



	if (hcd->localmem_pool)

		ohci->hcca = gen_pool_dma_alloc(hcd->localmem_pool,

						sizeof(*ohci->hcca),

						&ohci->hcca_dma);

	else

		ohci->hcca = dma_alloc_coherent(hcd->self.controller,

			sizeof(*ohci->hcca), &ohci->hcca_dma, GFP_KERNEL);

						sizeof(*ohci->hcca),

						&ohci->hcca_dma,

						GFP_KERNEL);

	if (!ohci->hcca)

		return -ENOMEM;
@@ -990,8 +998,13 @@ static void ohci_stop (struct usb_hcd *hcd) 
	remove_debug_files (ohci);

	ohci_mem_cleanup (ohci);

	if (ohci->hcca) {

		if (hcd->localmem_pool)

			gen_pool_free(hcd->localmem_pool,

				      (unsigned long)ohci->hcca,

				      sizeof(*ohci->hcca));

		else

			dma_free_coherent(hcd->self.controller,

				sizeof *ohci->hcca,

					  sizeof(*ohci->hcca),

					  ohci->hcca, ohci->hcca_dma);

		ohci->hcca = NULL;

		ohci->hcca_dma = 0;

drivers/usb/host/ohci-mem.c

+31 −4
Original line number Diff line number Diff line
@@ -36,6 +36,13 @@ static void ohci_hcd_init (struct ohci_hcd *ohci) 


static int ohci_mem_init (struct ohci_hcd *ohci)

{

	/*

	 * HCs with local memory allocate from localmem_pool so there's

	 * no need to create the below dma pools.

	 */

	if (ohci_to_hcd(ohci)->localmem_pool)

		return 0;



	ohci->td_cache = dma_pool_create ("ohci_td",

		ohci_to_hcd(ohci)->self.controller,

		sizeof (struct td),
@@ -84,7 +91,11 @@ td_alloc (struct ohci_hcd *hc, gfp_t mem_flags) 
{

	dma_addr_t	dma;

	struct td	*td;

	struct usb_hcd	*hcd = ohci_to_hcd(hc);



	if (hcd->localmem_pool)

		td = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*td), &dma);

	else

		td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma);

	if (td) {

		/* in case hc fetches it, make it look dead */
@@ -99,6 +110,7 @@ static void 
td_free (struct ohci_hcd *hc, struct td *td)

{

	struct td	**prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];

	struct usb_hcd	*hcd = ohci_to_hcd(hc);



	while (*prev && *prev != td)

		prev = &(*prev)->td_hash;
@@ -106,6 +118,11 @@ td_free (struct ohci_hcd *hc, struct td *td) 
		*prev = td->td_hash;

	else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)

		ohci_dbg (hc, "no hash for td %p\n", td);



	if (hcd->localmem_pool)

		gen_pool_free(hcd->localmem_pool, (unsigned long)td,

			      sizeof(*td));

	else

		dma_pool_free(hc->td_cache, td, td->td_dma);

}
@@ -117,7 +134,11 @@ ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags) 
{

	dma_addr_t	dma;

	struct ed	*ed;

	struct usb_hcd	*hcd = ohci_to_hcd(hc);



	if (hcd->localmem_pool)

		ed = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*ed), &dma);

	else

		ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma);

	if (ed) {

		INIT_LIST_HEAD (&ed->td_list);
@@ -129,6 +150,12 @@ ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags) 
static void

ed_free (struct ohci_hcd *hc, struct ed *ed)

{

	struct usb_hcd	*hcd = ohci_to_hcd(hc);



	if (hcd->localmem_pool)

		gen_pool_free(hcd->localmem_pool, (unsigned long)ed,

			      sizeof(*ed));

	else

		dma_pool_free(hc->ed_cache, ed, ed->dma);

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE