Commit 80f02512 authored by Leonardo Bras's avatar Leonardo Bras Committed by Michael Ellerman
Browse files

powerpc/pseries/iommu: Update call to ibm, query-pe-dma-windows 



>From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can make the number of
outputs from "ibm,query-pe-dma-windows" go from 5 to 6.

This change of output size is meant to expand the address size of
largest_available_block PE TCE from 32-bit to 64-bit, which ends up
shifting page_size and migration_capable.

This ends up requiring the update of
ddw_query_response->largest_available_block from u32 to u64, and manually
assigning the values from the buffer into this struct, according to
output size.

Also, a routine was created for helping reading the ddw extensions as
suggested by LoPAR: First reading the size of the extension array from
index 0, checking if the property exists, and then returning it's value.

Signed-off-by: default avatarLeonardo Bras <leobras.c@gmail.com>
Tested-by: default avatarDavid Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-3-leobras.c@gmail.com
parent cac3e629

arch/powerpc/platforms/pseries/iommu.c

+81 −10
Original line number Diff line number Diff line
@@ -47,6 +47,12 @@ enum { 
	DDW_APPLICABLE_SIZE

};



enum {

	DDW_EXT_SIZE = 0,

	DDW_EXT_RESET_DMA_WIN = 1,

	DDW_EXT_QUERY_OUT_SIZE = 2

};



static struct iommu_table_group *iommu_pseries_alloc_group(int node)

{

	struct iommu_table_group *table_group;
@@ -342,7 +348,7 @@ struct direct_window { 
/* Dynamic DMA Window support */

struct ddw_query_response {

	u32 windows_available;

	u32 largest_available_block;

	u64 largest_available_block;

	u32 page_size;

	u32 migration_capable;

};
@@ -877,14 +883,62 @@ static int find_existing_ddw_windows(void) 
}

machine_arch_initcall(pseries, find_existing_ddw_windows);



/**

 * ddw_read_ext - Get the value of an DDW extension

 * @np:		device node from which the extension value is to be read.

 * @extnum:	index number of the extension.

 * @value:	pointer to return value, modified when extension is available.

 *

 * Checks if "ibm,ddw-extensions" exists for this node, and get the value

 * on index 'extnum'.

 * It can be used only to check if a property exists, passing value == NULL.

 *

 * Returns:

 *	0 if extension successfully read

 *	-EINVAL if the "ibm,ddw-extensions" does not exist,

 *	-ENODATA if "ibm,ddw-extensions" does not have a value, and

 *	-EOVERFLOW if "ibm,ddw-extensions" does not contain this extension.

 */

static inline int ddw_read_ext(const struct device_node *np, int extnum,

			       u32 *value)

{

	static const char propname[] = "ibm,ddw-extensions";

	u32 count;

	int ret;



	ret = of_property_read_u32_index(np, propname, DDW_EXT_SIZE, &count);

	if (ret)

		return ret;



	if (count < extnum)

		return -EOVERFLOW;



	if (!value)

		value = &count;



	return of_property_read_u32_index(np, propname, extnum, value);

}



static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail,

			struct ddw_query_response *query)

		     struct ddw_query_response *query,

		     struct device_node *parent)

{

	struct device_node *dn;

	struct pci_dn *pdn;

	u32 cfg_addr;

	u32 cfg_addr, ext_query, query_out[5];

	u64 buid;

	int ret;

	int ret, out_sz;



	/*

	 * From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can rule how many

	 * output parameters ibm,query-pe-dma-windows will have, ranging from

	 * 5 to 6.

	 */

	ret = ddw_read_ext(parent, DDW_EXT_QUERY_OUT_SIZE, &ext_query);

	if (!ret && ext_query == 1)

		out_sz = 6;

	else

		out_sz = 5;



	/*

	 * Get the config address and phb buid of the PE window.
@@ -897,11 +951,28 @@ static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail, 
	buid = pdn->phb->buid;

	cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8));



	ret = rtas_call(ddw_avail[DDW_QUERY_PE_DMA_WIN], 3, 5, (u32 *)query,

	ret = rtas_call(ddw_avail[DDW_QUERY_PE_DMA_WIN], 3, out_sz, query_out,

			cfg_addr, BUID_HI(buid), BUID_LO(buid));

	dev_info(&dev->dev, "ibm,query-pe-dma-windows(%x) %x %x %x"

		" returned %d\n", ddw_avail[DDW_QUERY_PE_DMA_WIN], cfg_addr,

		 BUID_HI(buid), BUID_LO(buid), ret);

	dev_info(&dev->dev, "ibm,query-pe-dma-windows(%x) %x %x %x returned %d\n",

		 ddw_avail[DDW_QUERY_PE_DMA_WIN], cfg_addr, BUID_HI(buid),

		 BUID_LO(buid), ret);



	switch (out_sz) {

	case 5:

		query->windows_available = query_out[0];

		query->largest_available_block = query_out[1];

		query->page_size = query_out[2];

		query->migration_capable = query_out[3];

		break;

	case 6:

		query->windows_available = query_out[0];

		query->largest_available_block = ((u64)query_out[1] << 32) |

						 query_out[2];

		query->page_size = query_out[3];

		query->migration_capable = query_out[4];

		break;

	}



	return ret;

}
@@ -1049,7 +1120,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) 
	 * of page sizes: supported and supported for migrate-dma.

	 */

	dn = pci_device_to_OF_node(dev);

	ret = query_ddw(dev, ddw_avail, &query);

	ret = query_ddw(dev, ddw_avail, &query, pdn);

	if (ret != 0)

		goto out_failed;
@@ -1077,7 +1148,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) 
	/* check largest block * page size > max memory hotplug addr */

	max_addr = ddw_memory_hotplug_max();

	if (query.largest_available_block < (max_addr >> page_shift)) {

		dev_dbg(&dev->dev, "can't map partition max 0x%llx with %u "

		dev_dbg(&dev->dev, "can't map partition max 0x%llx with %llu "

			  "%llu-sized pages\n", max_addr,  query.largest_available_block,

			  1ULL << page_shift);

		goto out_failed;

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