Commit 0c634baf authored by Leonardo Bras's avatar Leonardo Bras Committed by Michael Ellerman
Browse files

powerpc/pseries/iommu: Replace hard-coded page shift 



Some functions assume IOMMU page size can only be 4K (pageshift == 12).
Update them to accept any page size passed, so we can use 64K pages.

In the process, some defines like TCE_SHIFT were made obsolete, and then
removed.

IODA3 Revision 3.0_prd1 (OpenPowerFoundation), Figures 3.4 and 3.5 show
a RPN of 52-bit, and considers a 12-bit pageshift, so there should be
no need of using TCE_RPN_MASK, which masks out any bit after 40 in rpn.
It's usage removed from tce_build_pSeries(), tce_build_pSeriesLP(), and
tce_buildmulti_pSeriesLP().

Most places had a tbl struct, so using tbl->it_page_shift was simple.
tce_free_pSeriesLP() was a special case, since callers not always have a
tbl struct, so adding a tceshift parameter seems the right thing to do.

Signed-off-by: default avatarLeonardo Bras <leobras.c@gmail.com>
Reviewed-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: default avatarFrederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210817063929.38701-2-leobras.c@gmail.com
parent 9a245d0e

arch/powerpc/include/asm/tce.h

+0 −8
Original line number Diff line number Diff line
@@ -19,15 +19,7 @@ 
#define TCE_VB			0

#define TCE_PCI			1



/* TCE page size is 4096 bytes (1 << 12) */



#define TCE_SHIFT	12

#define TCE_PAGE_SIZE	(1 << TCE_SHIFT)



#define TCE_ENTRY_SIZE		8		/* each TCE is 64 bits */



#define TCE_RPN_MASK		0xfffffffffful  /* 40-bit RPN (4K pages) */

#define TCE_RPN_SHIFT		12

#define TCE_VALID		0x800		/* TCE valid */

#define TCE_ALLIO		0x400		/* TCE valid for all lpars */

#define TCE_PCI_WRITE		0x2		/* write from PCI allowed */

arch/powerpc/platforms/pseries/iommu.c

+23 −16
Original line number Diff line number Diff line
@@ -107,6 +107,8 @@ static int tce_build_pSeries(struct iommu_table *tbl, long index, 
	u64 proto_tce;

	__be64 *tcep;

	u64 rpn;

	const unsigned long tceshift = tbl->it_page_shift;

	const unsigned long pagesize = IOMMU_PAGE_SIZE(tbl);



	proto_tce = TCE_PCI_READ; // Read allowed
@@ -117,10 +119,10 @@ static int tce_build_pSeries(struct iommu_table *tbl, long index, 


	while (npages--) {

		/* can't move this out since we might cross MEMBLOCK boundary */

		rpn = __pa(uaddr) >> TCE_SHIFT;

		*tcep = cpu_to_be64(proto_tce | (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT);

		rpn = __pa(uaddr) >> tceshift;

		*tcep = cpu_to_be64(proto_tce | rpn << tceshift);



		uaddr += TCE_PAGE_SIZE;

		uaddr += pagesize;

		tcep++;

	}

	return 0;
@@ -146,7 +148,7 @@ static unsigned long tce_get_pseries(struct iommu_table *tbl, long index) 
	return be64_to_cpu(*tcep);

}



static void tce_free_pSeriesLP(unsigned long liobn, long, long);

static void tce_free_pSeriesLP(unsigned long liobn, long, long, long);

static void tce_freemulti_pSeriesLP(struct iommu_table*, long, long);



static int tce_build_pSeriesLP(unsigned long liobn, long tcenum, long tceshift,
@@ -166,12 +168,12 @@ static int tce_build_pSeriesLP(unsigned long liobn, long tcenum, long tceshift, 
		proto_tce |= TCE_PCI_WRITE;



	while (npages--) {

		tce = proto_tce | (rpn & TCE_RPN_MASK) << tceshift;

		tce = proto_tce | rpn << tceshift;

		rc = plpar_tce_put((u64)liobn, (u64)tcenum << tceshift, tce);



		if (unlikely(rc == H_NOT_ENOUGH_RESOURCES)) {

			ret = (int)rc;

			tce_free_pSeriesLP(liobn, tcenum_start,

			tce_free_pSeriesLP(liobn, tcenum_start, tceshift,

			                   (npages_start - (npages + 1)));

			break;

		}
@@ -205,10 +207,11 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, 
	long tcenum_start = tcenum, npages_start = npages;

	int ret = 0;

	unsigned long flags;

	const unsigned long tceshift = tbl->it_page_shift;



	if ((npages == 1) || !firmware_has_feature(FW_FEATURE_PUT_TCE_IND)) {

		return tce_build_pSeriesLP(tbl->it_index, tcenum,

					   tbl->it_page_shift, npages, uaddr,

					   tceshift, npages, uaddr,

		                           direction, attrs);

	}
@@ -225,13 +228,13 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, 
		if (!tcep) {

			local_irq_restore(flags);

			return tce_build_pSeriesLP(tbl->it_index, tcenum,

					tbl->it_page_shift,

					tceshift,

					npages, uaddr, direction, attrs);

		}

		__this_cpu_write(tce_page, tcep);

	}



	rpn = __pa(uaddr) >> TCE_SHIFT;

	rpn = __pa(uaddr) >> tceshift;

	proto_tce = TCE_PCI_READ;

	if (direction != DMA_TO_DEVICE)

		proto_tce |= TCE_PCI_WRITE;
@@ -245,12 +248,12 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, 
		limit = min_t(long, npages, 4096/TCE_ENTRY_SIZE);



		for (l = 0; l < limit; l++) {

			tcep[l] = cpu_to_be64(proto_tce | (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT);

			tcep[l] = cpu_to_be64(proto_tce | rpn << tceshift);

			rpn++;

		}



		rc = plpar_tce_put_indirect((u64)tbl->it_index,

					    (u64)tcenum << 12,

					    (u64)tcenum << tceshift,

					    (u64)__pa(tcep),

					    limit);
@@ -277,12 +280,13 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, 
	return ret;

}



static void tce_free_pSeriesLP(unsigned long liobn, long tcenum, long npages)

static void tce_free_pSeriesLP(unsigned long liobn, long tcenum, long tceshift,

			       long npages)

{

	u64 rc;



	while (npages--) {

		rc = plpar_tce_put((u64)liobn, (u64)tcenum << 12, 0);

		rc = plpar_tce_put((u64)liobn, (u64)tcenum << tceshift, 0);



		if (rc && printk_ratelimit()) {

			printk("tce_free_pSeriesLP: plpar_tce_put failed. rc=%lld\n", rc);
@@ -301,9 +305,11 @@ static void tce_freemulti_pSeriesLP(struct iommu_table *tbl, long tcenum, long n 
	u64 rc;



	if (!firmware_has_feature(FW_FEATURE_STUFF_TCE))

		return tce_free_pSeriesLP(tbl->it_index, tcenum, npages);

		return tce_free_pSeriesLP(tbl->it_index, tcenum,

					  tbl->it_page_shift, npages);



	rc = plpar_tce_stuff((u64)tbl->it_index, (u64)tcenum << 12, 0, npages);

	rc = plpar_tce_stuff((u64)tbl->it_index,

			     (u64)tcenum << tbl->it_page_shift, 0, npages);



	if (rc && printk_ratelimit()) {

		printk("tce_freemulti_pSeriesLP: plpar_tce_stuff failed\n");
@@ -319,7 +325,8 @@ static unsigned long tce_get_pSeriesLP(struct iommu_table *tbl, long tcenum) 
	u64 rc;

	unsigned long tce_ret;



	rc = plpar_tce_get((u64)tbl->it_index, (u64)tcenum << 12, &tce_ret);

	rc = plpar_tce_get((u64)tbl->it_index,

			   (u64)tcenum << tbl->it_page_shift, &tce_ret);



	if (rc && printk_ratelimit()) {

		printk("tce_get_pSeriesLP: plpar_tce_get failed. rc=%lld\n", rc);