Hi Tomasz,

On Thu, Aug 11, 2016 at 12:06:31PM +0200, Tomasz Nowicki wrote:

IORT shows representation of IO topology for ARM based systems. It describes how various components are connected together on parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapp...

Initial support allows to detect IORT table presence and save its root pointer obtained through acpi_get_table(). The pointer validity depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap is not set while using IORT nodes we would dereference unmapped pointers.

For the aforementioned reason call iort_table_detect() from acpi_init() which guarantees acpi_gbl_permanent_mmap to be set at that point.

We still need to get Rafael ACK on this, keeping in mind that the eg code parsing DMAR table relies on the same assumption.

[...]

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 445ce28..6cef2d1 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -521,4 +521,9 @@ config ACPI_CONFIGFS userspace. The configurable ACPI groups will be visible under /config/acpi, assuming configfs is mounted under /config. +if ARM64 +source "drivers/acpi/arm64/Kconfig"

Just curious: Why do you need a space ?

+endif

endif # ACPI diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 5ae9d85..e5ada78 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -105,3 +105,5 @@ obj-$(CONFIG_ACPI_CONFIGFS) += acpi_configfs.o video-objs += acpi_video.o video_detect.o obj-y += dptf/

+obj-$(CONFIG_ARM64) += arm64/ diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..fc818dc --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,6 @@ +# +# ACPI Configuration for ARM64 +#

+config IORT_TABLE

• bool

diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile new file mode 100644 index 0000000..d01be6f --- /dev/null +++ b/drivers/acpi/arm64/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_IORT_TABLE) += iort.o diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c new file mode 100644 index 0000000..f89056e --- /dev/null +++ b/drivers/acpi/arm64/iort.c @@ -0,0 +1,218 @@ +/*

• • Copyright (C) 2016, Semihalf
• • Author: Tomasz Nowicki tn@semihalf.com
• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • This file implements early detection/parsing of I/O mapping
• • reported to OS through firmware via I/O Remapping Table (IORT)
• • IORT document number: ARM DEN 0049A
• */

+#define pr_fmt(fmt) "ACPI: IORT: " fmt

+#include <linux/iort.h> +#include <linux/kernel.h> +#include <linux/pci.h>

+typedef acpi_status (*iort_find_node_callback)

• (struct acpi_iort_node *node, void *context);

+/* Root pointer to the mapped IORT table */ +static struct acpi_table_header *iort_table;

See above.

[...]

+void __init iort_table_detect(void) +{

• acpi_status status;
• status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table);
• if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {

• const char *msg = acpi_format_exception(status);
  

• pr_err("Failed to get table, %s\n", msg);
  

• }

+} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 85b7d07..55a84da 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -36,6 +36,7 @@ #ifdef CONFIG_X86 #include <asm/mpspec.h> #endif +#include <linux/iort.h> #include <linux/pci.h> #include <acpi/apei.h> #include <linux/dmi.h> @@ -1186,6 +1187,7 @@ static int __init acpi_init(void) } pci_mmcfg_late_init();

• iort_table_detect();

That's another bit we have to make sure Rafael is ok with, given that IORT is ARM64 specific (but we stub it out if it is not configured).

Having said that:

Reviewed-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com

acpi_scan_init(); acpi_ec_init(); acpi_debugfs_init(); diff --git a/include/linux/iort.h b/include/linux/iort.h new file mode 100644 index 0000000..cde6809 --- /dev/null +++ b/include/linux/iort.h @@ -0,0 +1,30 @@ +/*

• • Copyright (C) 2016, Semihalf
• • Author: Tomasz Nowicki tn@semihalf.com
• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • You should have received a copy of the GNU General Public License along with
• • this program; if not, write to the Free Software Foundation, Inc., 59 Temple
• • Place - Suite 330, Boston, MA 02111-1307 USA.
• */

+#ifndef __IORT_H__ +#define __IORT_H__

+#include <linux/acpi.h>

+#ifdef CONFIG_IORT_TABLE +void iort_table_detect(void); +#else +static inline void iort_table_detect(void) { } +#endif

+#endif /* __IORT_H__ */

1.9.1

Hi Rafael,

On Thu, Aug 18, 2016 at 08:25:20AM +0200, Tomasz Nowicki wrote:

On 12.08.2016 18:33, Lorenzo Pieralisi wrote:

...

Hi Tomasz,

On Thu, Aug 11, 2016 at 12:06:31PM +0200, Tomasz Nowicki wrote:

...

IORT shows representation of IO topology for ARM based systems. It describes how various components are connected together on parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapp...

Initial support allows to detect IORT table presence and save its root pointer obtained through acpi_get_table(). The pointer validity depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap is not set while using IORT nodes we would dereference unmapped pointers.

For the aforementioned reason call iort_table_detect() from acpi_init() which guarantees acpi_gbl_permanent_mmap to be set at that point.

We still need to get Rafael ACK on this, keeping in mind that the eg code parsing DMAR table relies on the same assumption.

Exactly.

Rafael, can you please have a look ?

A gentle reminder, this patch is gating this series and requires your review, please let us know what you think.

Thank you, Lorenzo

...

[...]

...

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 445ce28..6cef2d1 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -521,4 +521,9 @@ config ACPI_CONFIGFS userspace. The configurable ACPI groups will be visible under /config/acpi, assuming configfs is mounted under /config.

+if ARM64 +source "drivers/acpi/arm64/Kconfig"

Just curious: Why do you need a space ?

No good reason, it will disappear for next version.

...

...

+endif

endif # ACPI diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 5ae9d85..e5ada78 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -105,3 +105,5 @@ obj-$(CONFIG_ACPI_CONFIGFS) += acpi_configfs.o

video-objs += acpi_video.o video_detect.o obj-y += dptf/

+obj-$(CONFIG_ARM64) += arm64/ diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..fc818dc --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,6 @@ +# +# ACPI Configuration for ARM64 +#

+config IORT_TABLE

• bool

diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile new file mode 100644 index 0000000..d01be6f --- /dev/null +++ b/drivers/acpi/arm64/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_IORT_TABLE) += iort.o diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c new file mode 100644 index 0000000..f89056e --- /dev/null +++ b/drivers/acpi/arm64/iort.c @@ -0,0 +1,218 @@ +/*

• • Copyright (C) 2016, Semihalf
• • Author: Tomasz Nowicki tn@semihalf.com
• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • This file implements early detection/parsing of I/O mapping
• • reported to OS through firmware via I/O Remapping Table (IORT)
• • IORT document number: ARM DEN 0049A
• */

+#define pr_fmt(fmt) "ACPI: IORT: " fmt

+#include <linux/iort.h> +#include <linux/kernel.h> +#include <linux/pci.h>

+typedef acpi_status (*iort_find_node_callback)

• (struct acpi_iort_node *node, void *context);

+/* Root pointer to the mapped IORT table */ +static struct acpi_table_header *iort_table;

See above.

[...]

...

+void __init iort_table_detect(void) +{

• acpi_status status;
• status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table);
• if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {

• const char *msg = acpi_format_exception(status);
  

• pr_err("Failed to get table, %s\n", msg);
  

• }

+} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 85b7d07..55a84da 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -36,6 +36,7 @@ #ifdef CONFIG_X86 #include <asm/mpspec.h> #endif +#include <linux/iort.h> #include <linux/pci.h> #include <acpi/apei.h> #include <linux/dmi.h> @@ -1186,6 +1187,7 @@ static int __init acpi_init(void) }

pci_mmcfg_late_init();

• iort_table_detect();

That's another bit we have to make sure Rafael is ok with, given that IORT is ARM64 specific (but we stub it out if it is not configured).

Having said that:

Reviewed-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com

Thanks for your time.

Tomasz

On Thu, Aug 18, 2016 at 06:55:50PM +0800, Dennis Chen wrote:

[...]

...

+static struct acpi_iort_node * +iort_scan_node(enum acpi_iort_node_type type,

•       iort_find_node_callback callback, void *context)
  

+{

• struct acpi_iort_node *iort_node, *iort_end;
• struct acpi_table_iort *iort;
• int i;
• /* Get the first IORT node */
• iort = (struct acpi_table_iort *)iort_table;

Here, the same as I comments on Lorenzo's patch. If IORT is missed in the firmware, then iort_table will be NULL, result in kernel panic in the codes followed.

The pointer is checked in the functions that are visible to other compilation units before calling this function:

iort_msi_map_rid() iort_get_device_domain()

I missed to check it when I added iort_node_match() and iort_iommu_configure() though, which makes me think that it is probably better to move the iort_table pointer check to iort_scan_node() so that it is done in one single place instead of adding it to all given external interfaces.

Lorenzo

Thanks, Dennis

...

• iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort,

• 		 iort->node_offset);
  

• iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,

• 		iort_table->length);
  

• for (i = 0; i < iort->node_count; i++) {

• if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND,
  

• 	       "IORT node pointer overflows, bad table!\n"))
  

• 	return NULL;
  

• if (iort_node->type == type) {
  

• 	if (ACPI_SUCCESS(callback(iort_node, context)))
  

• 		return iort_node;
  

• }
  

• iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node,
  

• 			 iort_node->length);
  

• }
• return NULL;

+}

+static acpi_status +iort_match_node_callback(struct acpi_iort_node *node, void *context) +{

• struct device *dev = context;
• switch (node->type) {
• case ACPI_IORT_NODE_NAMED_COMPONENT: {

• struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  

• struct acpi_device *adev = to_acpi_device_node(dev->fwnode);
  

• struct acpi_iort_named_component *ncomp;
  

• if (!adev)
  

• 	break;
  

• ncomp = (struct acpi_iort_named_component *)node->node_data;
  

• if (ACPI_FAILURE(acpi_get_name(adev->handle,
  

• 			       ACPI_FULL_PATHNAME, &buffer))) {
  

• 	dev_warn(dev, "Can't get device full path name\n");
  

• } else {
  

• 	int match;
  

• 	match = !strcmp(ncomp->device_name, buffer.pointer);
  

• 	acpi_os_free(buffer.pointer);
  

• 	if (match)
  

• 		return AE_OK;
  

• }
  

• break;
  

• }
• case ACPI_IORT_NODE_PCI_ROOT_COMPLEX: {

• struct acpi_iort_root_complex *pci_rc;
  

• struct pci_bus *bus;
  

• bus = to_pci_bus(dev);
  

• pci_rc = (struct acpi_iort_root_complex *)node->node_data;
  

• /*
  

•  * It is assumed that PCI segment numbers maps one-to-one
  

•  * with root complexes. Each segment number can represent only
  

•  * one root complex.
  

•  */
  

• if (pci_rc->pci_segment_number == pci_domain_nr(bus))
  

• 	return AE_OK;
  

• break;
  

• }
• }
• return AE_NOT_FOUND;

+}

+static int +iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, u32 *rid_out) +{

• /* Single mapping does not care for input id */
• if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {

• if (type == ACPI_IORT_NODE_NAMED_COMPONENT ||
  

•     type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
  

• 	*rid_out = map->output_base;
  

• 	return 0;
  

• }
  

• pr_warn(FW_BUG "[map %p] SINGLE MAPPING flag not allowed for node type %d, skipping ID map\n",
  

• 	map, type);
  

• return -ENXIO;
  

• }
• if (rid_in < map->input_base ||

•    (rid_in >= map->input_base + map->id_count))
  

• return -ENXIO;
  

• *rid_out = map->output_base + (rid_in - map->input_base);
• return 0;

+}

+static struct acpi_iort_node * +iort_node_map_rid(struct acpi_iort_node *node, u32 rid_in,

•   u32 *rid_out, u8 type)
  

+{

• u32 rid = rid_in;
• /* Parse the ID mapping tree to find specified node type */
• while (node) {

• struct acpi_iort_id_mapping *map;
  

• int i;
  

• if (node->type == type) {
  

• 	if (rid_out)
  

• 		*rid_out = rid;
  

• 	return node;
  

• }
  

• if (!node->mapping_offset || !node->mapping_count)
  

• 	goto fail_map;
  

• map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
  

• 		   node->mapping_offset);
  

• /* Firmware bug! */
  

• if (!map->output_reference) {
  

• 	pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n",
  

• 	       node, node->type);
  

• 	goto fail_map;
  

• }
  

• /* Do the RID translation */
  

• for (i = 0; i < node->mapping_count; i++, map++) {
  

• 	if (!iort_id_map(map, node->type, rid, &rid))
  

• 		break;
  

• }
  

• if (i == node->mapping_count)
  

• 	goto fail_map;
  

• node = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
  

• 		    map->output_reference);
  

• }

+fail_map:

• /* Map input RID to output RID unchanged on mapping failure*/
• if (rid_out)

• *rid_out = rid_in;
  

• return NULL;

+}

+static struct acpi_iort_node * +iort_find_dev_node(struct device *dev) +{

• struct pci_bus *pbus;
• if (!dev_is_pci(dev))

• return iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
  

• 		      iort_match_node_callback, dev);
  

• /* Find a PCI root bus */
• pbus = to_pci_dev(dev)->bus;
• while (!pci_is_root_bus(pbus))

• pbus = pbus->parent;
  

• return iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,

• 	      iort_match_node_callback, &pbus->dev);
  

+}

+void __init iort_table_detect(void) +{

• acpi_status status;
• status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table);
• if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {

• const char *msg = acpi_format_exception(status);
  

• pr_err("Failed to get table, %s\n", msg);
  

• }

+} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 85b7d07..55a84da 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -36,6 +36,7 @@ #ifdef CONFIG_X86 #include <asm/mpspec.h> #endif +#include <linux/iort.h> #include <linux/pci.h> #include <acpi/apei.h> #include <linux/dmi.h> @@ -1186,6 +1187,7 @@ static int __init acpi_init(void) } pci_mmcfg_late_init();

• iort_table_detect(); acpi_scan_init(); acpi_ec_init(); acpi_debugfs_init();

diff --git a/include/linux/iort.h b/include/linux/iort.h new file mode 100644 index 0000000..cde6809 --- /dev/null +++ b/include/linux/iort.h @@ -0,0 +1,30 @@ +/*

• • Copyright (C) 2016, Semihalf
• • Author: Tomasz Nowicki tn@semihalf.com
• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • You should have received a copy of the GNU General Public License along with
• • this program; if not, write to the Free Software Foundation, Inc., 59 Temple
• • Place - Suite 330, Boston, MA 02111-1307 USA.
• */

+#ifndef __IORT_H__ +#define __IORT_H__

+#include <linux/acpi.h>

+#ifdef CONFIG_IORT_TABLE +void iort_table_detect(void); +#else +static inline void iort_table_detect(void) { } +#endif

+#endif /* __IORT_H__ */

1.9.1

-- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

Hi Tomasz,

On 11 August 2016 at 18:06, Tomasz Nowicki tn@semihalf.com wrote:

IORT shows representation of IO topology for ARM based systems. It describes how various components are connected together on parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapp...

Initial support allows to detect IORT table presence and save its root pointer obtained through acpi_get_table(). The pointer validity depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap is not set while using IORT nodes we would dereference unmapped pointers.

For the aforementioned reason call iort_table_detect() from acpi_init() which guarantees acpi_gbl_permanent_mmap to be set at that point.

Add generic helpers which are helpful for scanning and retrieving information from IORT table content. List of the most important helpers:

• iort_find_dev_node() finds IORT node for a given device
• iort_node_map_rid() maps device RID and returns IORT node which provides final translation

IORT support is placed under drivers/acpi/arm64/ new directory due to its ARM64 specific nature. The code there is considered only for ARM64. The long term plan is to keep all ARM64 specific tables support in this place e.g. GTDT table.

Signed-off-by: Tomasz Nowicki tn@semihalf.com Reviewed-by: Hanjun Guo hanjun.guo@linaro.org

---

drivers/acpi/Kconfig | 5 + drivers/acpi/Makefile | 2 + drivers/acpi/arm64/Kconfig | 6 ++ drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/iort.c | 218 ++++++++++++++++++++++++++++++++++++++++++++ drivers/acpi/bus.c | 2 + include/linux/iort.h | 30 ++++++ 7 files changed, 264 insertions(+) create mode 100644 drivers/acpi/arm64/Kconfig create mode 100644 drivers/acpi/arm64/Makefile create mode 100644 drivers/acpi/arm64/iort.c create mode 100644 include/linux/iort.h

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 445ce28..6cef2d1 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -521,4 +521,9 @@ config ACPI_CONFIGFS userspace. The configurable ACPI groups will be visible under /config/acpi, assuming configfs is mounted under /config.

+if ARM64 +source "drivers/acpi/arm64/Kconfig"

+endif

endif # ACPI diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 5ae9d85..e5ada78 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -105,3 +105,5 @@ obj-$(CONFIG_ACPI_CONFIGFS) += acpi_configfs.o

video-objs += acpi_video.o video_detect.o obj-y += dptf/

+obj-$(CONFIG_ARM64) += arm64/ diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..fc818dc --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,6 @@ +# +# ACPI Configuration for ARM64 +#

+config IORT_TABLE

Sorry for nit-picking, but is that better to use ACPI_IORT or maybe ARM64__IORT ??

•   bool
  

diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile new file mode 100644 index 0000000..d01be6f --- /dev/null +++ b/drivers/acpi/arm64/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_IORT_TABLE) += iort.o diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c new file mode 100644 index 0000000..f89056e --- /dev/null +++ b/drivers/acpi/arm64/iort.c @@ -0,0 +1,218 @@ +/*

• • Copyright (C) 2016, Semihalf

• • Author: Tomasz Nowicki <tn@semihalf.com>
    

• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • This file implements early detection/parsing of I/O mapping
• • reported to OS through firmware via I/O Remapping Table (IORT)
• • IORT document number: ARM DEN 0049A
• */

+#define pr_fmt(fmt) "ACPI: IORT: " fmt

+#include <linux/iort.h> +#include <linux/kernel.h> +#include <linux/pci.h>

+typedef acpi_status (*iort_find_node_callback)

•   (struct acpi_iort_node *node, void *context);
  

+/* Root pointer to the mapped IORT table */ +static struct acpi_table_header *iort_table;

+static struct acpi_iort_node * +iort_scan_node(enum acpi_iort_node_type type,

•          iort_find_node_callback callback, void *context)
  

+{

•   struct acpi_iort_node *iort_node, *iort_end;
  

•   struct acpi_table_iort *iort;
  

•   int i;
  

•   /* Get the first IORT node */
  

•   iort = (struct acpi_table_iort *)iort_table;
  

•   iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort,
  

•                            iort->node_offset);
  

•   iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
  

•                           iort_table->length);
  

•   for (i = 0; i < iort->node_count; i++) {
  

•           if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND,
  

•                          "IORT node pointer overflows, bad table!\n"))
  

•                   return NULL;
  

•           if (iort_node->type == type) {
  

•                   if (ACPI_SUCCESS(callback(iort_node, context)))
  

•                           return iort_node;
  

•           }
  

•           iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node,
  

•                                    iort_node->length);
  

•   }
  

•   return NULL;
  

+}

+static acpi_status +iort_match_node_callback(struct acpi_iort_node *node, void *context) +{

•   struct device *dev = context;
  

•   switch (node->type) {
  

•   case ACPI_IORT_NODE_NAMED_COMPONENT: {
  

•           struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  

•           struct acpi_device *adev = to_acpi_device_node(dev->fwnode);
  

•           struct acpi_iort_named_component *ncomp;
  

•           if (!adev)
  

•                   break;
  

•           ncomp = (struct acpi_iort_named_component *)node->node_data;
  

•           if (ACPI_FAILURE(acpi_get_name(adev->handle,
  

•                                          ACPI_FULL_PATHNAME, &buffer))) {
  

•                   dev_warn(dev, "Can't get device full path name\n");
  

•           } else {
  

•                   int match;
  

•                   match = !strcmp(ncomp->device_name, buffer.pointer);
  

•                   acpi_os_free(buffer.pointer);
  

•                   if (match)
  

•                           return AE_OK;
  

•           }
  

•           break;
  

•   }
  

•   case ACPI_IORT_NODE_PCI_ROOT_COMPLEX: {
  

•           struct acpi_iort_root_complex *pci_rc;
  

•           struct pci_bus *bus;
  

•           bus = to_pci_bus(dev);
  

•           pci_rc = (struct acpi_iort_root_complex *)node->node_data;
  

•           /*
  

•            * It is assumed that PCI segment numbers maps one-to-one
  

•            * with root complexes. Each segment number can represent only
  

•            * one root complex.
  

•            */
  

•           if (pci_rc->pci_segment_number == pci_domain_nr(bus))
  

•                   return AE_OK;
  

•           break;
  

•   }
  

•   }
  

•   return AE_NOT_FOUND;
  

+}

+static int +iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, u32 *rid_out) +{

•   /* Single mapping does not care for input id */
  

•   if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
  

•           if (type == ACPI_IORT_NODE_NAMED_COMPONENT ||
  

•               type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
  

•                   *rid_out = map->output_base;
  

•                   return 0;
  

•           }
  

•           pr_warn(FW_BUG "[map %p] SINGLE MAPPING flag not allowed for node type %d, skipping ID map\n",
  

•                   map, type);
  

•           return -ENXIO;
  

•   }
  

•   if (rid_in < map->input_base ||
  

•       (rid_in >= map->input_base + map->id_count))
  

•           return -ENXIO;
  

•   *rid_out = map->output_base + (rid_in - map->input_base);
  

•   return 0;
  

+}

+static struct acpi_iort_node * +iort_node_map_rid(struct acpi_iort_node *node, u32 rid_in,

•             u32 *rid_out, u8 type)
  

+{

•   u32 rid = rid_in;
  

•   /* Parse the ID mapping tree to find specified node type */
  

•   while (node) {
  

•           struct acpi_iort_id_mapping *map;
  

•           int i;
  

•           if (node->type == type) {
  

•                   if (rid_out)
  

•                           *rid_out = rid;
  

•                   return node;
  

•           }
  

•           if (!node->mapping_offset || !node->mapping_count)
  

•                   goto fail_map;
  

•           map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
  

•                              node->mapping_offset);
  

•           /* Firmware bug! */
  

•           if (!map->output_reference) {
  

•                   pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n",
  

•                          node, node->type);
  

•                   goto fail_map;
  

•           }
  

•           /* Do the RID translation */
  

•           for (i = 0; i < node->mapping_count; i++, map++) {
  

•                   if (!iort_id_map(map, node->type, rid, &rid))
  

•                           break;
  

•           }
  

•           if (i == node->mapping_count)
  

•                   goto fail_map;
  

•           node = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
  

•                               map->output_reference);
  

•   }
  

+fail_map:

•   /* Map input RID to output RID unchanged on mapping failure*/
  

•   if (rid_out)
  

•           *rid_out = rid_in;
  

•   return NULL;
  

+}

+static struct acpi_iort_node * +iort_find_dev_node(struct device *dev) +{

•   struct pci_bus *pbus;
  

•   if (!dev_is_pci(dev))
  

•           return iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
  

•                                 iort_match_node_callback, dev);
  

•   /* Find a PCI root bus */
  

•   pbus = to_pci_dev(dev)->bus;
  

•   while (!pci_is_root_bus(pbus))
  

•           pbus = pbus->parent;
  

•   return iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
  

•                         iort_match_node_callback, &pbus->dev);
  

+}

+void __init iort_table_detect(void) +{

•   acpi_status status;
  

•   status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table);
  

•   if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  

•           const char *msg = acpi_format_exception(status);
  

•           pr_err("Failed to get table, %s\n", msg);
  

•   }
  

+} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 85b7d07..55a84da 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -36,6 +36,7 @@ #ifdef CONFIG_X86 #include <asm/mpspec.h> #endif +#include <linux/iort.h> #include <linux/pci.h> #include <acpi/apei.h> #include <linux/dmi.h> @@ -1186,6 +1187,7 @@ static int __init acpi_init(void) }

    pci_mmcfg_late_init();

•   iort_table_detect();
    acpi_scan_init();
    acpi_ec_init();
    acpi_debugfs_init();
  

diff --git a/include/linux/iort.h b/include/linux/iort.h new file mode 100644 index 0000000..cde6809 --- /dev/null +++ b/include/linux/iort.h @@ -0,0 +1,30 @@ +/*

• • Copyright (C) 2016, Semihalf

• • Author: Tomasz Nowicki <tn@semihalf.com>
    

• • This program is free software; you can redistribute it and/or modify it
• • under the terms and conditions of the GNU General Public License,
• • version 2, as published by the Free Software Foundation.
• • This program is distributed in the hope it will be useful, but WITHOUT
• • ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
• • FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
• • more details.
• • You should have received a copy of the GNU General Public License along with
• • this program; if not, write to the Free Software Foundation, Inc., 59 Temple
• • Place - Suite 330, Boston, MA 02111-1307 USA.
• */

+#ifndef __IORT_H__ +#define __IORT_H__

+#include <linux/acpi.h>

+#ifdef CONFIG_IORT_TABLE +void iort_table_detect(void); +#else +static inline void iort_table_detect(void) { } +#endif

+#endif /* __IORT_H__ */

1.9.1

---

Linaro-acpi mailing list Linaro-acpi@lists.linaro.org https://lists.linaro.org/mailman/listinfo/linaro-acpi

Hi Tomasz,

On 5 September 2016 at 14:12, Tomasz Nowicki tn@semihalf.com wrote:

On 02.09.2016 13:52, Fu Wei wrote:

...

Hi Tomasz,

On 11 August 2016 at 18:06, Tomasz Nowicki tn@semihalf.com wrote:

...

IORT shows representation of IO topology for ARM based systems. It describes how various components are connected together on parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec.

http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapp...

Initial support allows to detect IORT table presence and save its root pointer obtained through acpi_get_table(). The pointer validity depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap is not set while using IORT nodes we would dereference unmapped pointers.

For the aforementioned reason call iort_table_detect() from acpi_init() which guarantees acpi_gbl_permanent_mmap to be set at that point.

Add generic helpers which are helpful for scanning and retrieving information from IORT table content. List of the most important helpers:

• iort_find_dev_node() finds IORT node for a given device
• iort_node_map_rid() maps device RID and returns IORT node which

provides final translation

IORT support is placed under drivers/acpi/arm64/ new directory due to its ARM64 specific nature. The code there is considered only for ARM64. The long term plan is to keep all ARM64 specific tables support in this place e.g. GTDT table.

Signed-off-by: Tomasz Nowicki tn@semihalf.com Reviewed-by: Hanjun Guo hanjun.guo@linaro.org

---

drivers/acpi/Kconfig | 5 + drivers/acpi/Makefile | 2 + drivers/acpi/arm64/Kconfig | 6 ++ drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/iort.c | 218 ++++++++++++++++++++++++++++++++++++++++++++ drivers/acpi/bus.c | 2 + include/linux/iort.h | 30 ++++++ 7 files changed, 264 insertions(+) create mode 100644 drivers/acpi/arm64/Kconfig create mode 100644 drivers/acpi/arm64/Makefile create mode 100644 drivers/acpi/arm64/iort.c create mode 100644 include/linux/iort.h

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 445ce28..6cef2d1 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -521,4 +521,9 @@ config ACPI_CONFIGFS userspace. The configurable ACPI groups will be visible under /config/acpi, assuming configfs is mounted under /config.

+if ARM64 +source "drivers/acpi/arm64/Kconfig"

+endif

endif # ACPI diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 5ae9d85..e5ada78 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -105,3 +105,5 @@ obj-$(CONFIG_ACPI_CONFIGFS) += acpi_configfs.o

video-objs += acpi_video.o video_detect.o obj-y += dptf/

+obj-$(CONFIG_ARM64) += arm64/ diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 0000000..fc818dc --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,6 @@ +# +# ACPI Configuration for ARM64 +#

+config IORT_TABLE

Sorry for nit-picking, but is that better to use ACPI_IORT or maybe ARM64__IORT ??

ACPI_IORT sounds good.

Thanks, Tomasz :-) I have rebaseed my GTDT patchset on your v8 patchset, But before I post my new patchset, I hope we can harmonize with each other on these:

1. ACPI_IORT -- ACPI_GTDT 2. for the file name, maybe can follow "/drivers/acpi/acpi_*.c" like acpi_iort.c and acpi_gtdt.c or follow "/drivers/acpi/apei/*.c" like iort.c and gtdt.c.

looking forward to you new patchset :-) Thanks :-)

Tomasz

On Thu, Aug 11, 2016 at 12:06:32PM +0200, Tomasz Nowicki wrote:

[...]

+/**

• • iort_register_domain_token() - register domain token and related ITS ID
• • to the list from where we can get it back later on.
• • @trans_id: ITS ID.
• • @fw_node: Domain token.
• • Returns: 0 on success, -ENOMEM if no memory when allocating list element
• */

+int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node) +{

• struct iort_its_msi_chip *its_msi_chip;
• its_msi_chip = kzalloc(sizeof(*its_msi_chip), GFP_KERNEL);

I spotted this while reworking my ARM SMMU series, this may sleep and that's no good given that we call it within the acpi_probe_lock.

Same goes for irq_domain_alloc_fwnode() (that we call in gic_v2_acpi_init()), we have got to fix this usage, I will see with Marc what's the best way to do it.

Lorenzo

• if (!its_msi_chip)

• return -ENOMEM;
  

• its_msi_chip->fw_node = fw_node;
• its_msi_chip->translation_id = trans_id;
• spin_lock(&iort_msi_chip_lock);
• list_add(&its_msi_chip->list, &iort_msi_chip_list);
• spin_unlock(&iort_msi_chip_lock);
• return 0;

+}

+/**

• • iort_deregister_domain_token() - Deregister domain token based on ITS ID
• • @trans_id: ITS ID.
• • Returns: none.
• */

+void iort_deregister_domain_token(int trans_id) +{

• struct iort_its_msi_chip *its_msi_chip, *t;
• spin_lock(&iort_msi_chip_lock);
• list_for_each_entry_safe(its_msi_chip, t, &iort_msi_chip_list, list) {

• if (its_msi_chip->translation_id == trans_id) {
  

• 	list_del(&its_msi_chip->list);
  

• 	kfree(its_msi_chip);
  

• 	break;
  

• }
  

• }
• spin_unlock(&iort_msi_chip_lock);

+}

+/**

• • iort_find_domain_token() - Find domain token based on given ITS ID
• • @trans_id: ITS ID.
• • Returns: domain token when find on the list, NULL otherwise
• */

+struct fwnode_handle *iort_find_domain_token(int trans_id) +{

• struct fwnode_handle *fw_node = NULL;
• struct iort_its_msi_chip *its_msi_chip;
• spin_lock(&iort_msi_chip_lock);
• list_for_each_entry(its_msi_chip, &iort_msi_chip_list, list) {

• if (its_msi_chip->translation_id == trans_id) {
  

• 	fw_node = its_msi_chip->fw_node;
  

• 	break;
  

• }
  

• }
• spin_unlock(&iort_msi_chip_lock);
• return fw_node;

+}

static struct acpi_iort_node * iort_scan_node(enum acpi_iort_node_type type, iort_find_node_callback callback, void *context) @@ -206,6 +285,96 @@ iort_find_dev_node(struct device *dev) iort_match_node_callback, &pbus->dev); } +/**

• • iort_msi_map_rid() - Map a MSI requester ID for a device
• • @dev: The device for which the mapping is to be done.
• • @req_id: The device requester ID.
• • Returns: mapped MSI RID on success, input requester ID otherwise
• */

+u32 iort_msi_map_rid(struct device *dev, u32 req_id) +{

• struct acpi_iort_node *node;
• u32 dev_id;
• if (!iort_table)

• return req_id;
  

• node = iort_find_dev_node(dev);
• if (!node) {

• dev_err(dev, "can't find related IORT node\n");
  

• return req_id;
  

• }
• iort_node_map_rid(node, req_id, &dev_id, ACPI_IORT_NODE_ITS_GROUP);
• return dev_id;

+}

+/**

• • iort_dev_find_its_id() - Find the ITS identifier for a device
• • @dev: The device.
• • @idx: Index of the ITS identifier list.
• • @its_id: ITS identifier.
• • Returns: 0 on success, appropriate error value otherwise
• */

+static int +iort_dev_find_its_id(struct device *dev, u32 req_id, unsigned int idx,

•      int *its_id)
  

+{

• struct acpi_iort_its_group *its;
• struct acpi_iort_node *node;
• node = iort_find_dev_node(dev);
• if (!node) {

• dev_err(dev, "can't find related IORT node\n");
  

• return -ENXIO;
  

• }
• node = iort_node_map_rid(node, req_id, NULL, ACPI_IORT_NODE_ITS_GROUP);
• if (!node) {

• dev_err(dev, "can't find related ITS node\n");
  

• return -ENXIO;
  

• }
• /* Move to ITS specific data */
• its = (struct acpi_iort_its_group *)node->node_data;
• if (idx > its->its_count) {

• dev_err(dev, "requested ITS ID index [%d] is greater than available [%d]\n",
  

• 	idx, its->its_count);
  

• return -ENXIO;
  

• }
• *its_id = its->identifiers[idx];
• return 0;

+}

+/**

• • iort_get_device_domain() - Find MSI domain related to a device
• • @dev: The device.
• • @req_id: Requester ID for the device.
• • Returns: the MSI domain for this device, NULL otherwise
• */

+struct irq_domain * +iort_get_device_domain(struct device *dev, u32 req_id) +{

• static struct fwnode_handle *handle;
• int its_id;
• if (!iort_table)

• return NULL;
  

• if (iort_dev_find_its_id(dev, req_id, 0, &its_id))

• return NULL;
  

• handle = iort_find_domain_token(its_id);
• if (!handle)

• return NULL;
  

• return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);

+}

void __init iort_table_detect(void) { acpi_status status; diff --git a/include/linux/iort.h b/include/linux/iort.h index cde6809..d7daba1 100644 --- a/include/linux/iort.h +++ b/include/linux/iort.h @@ -20,11 +20,22 @@ #define __IORT_H__ #include <linux/acpi.h> +#include <linux/fwnode.h> +#include <linux/irqdomain.h> +int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node); +void iort_deregister_domain_token(int trans_id); +struct fwnode_handle *iort_find_domain_token(int trans_id); #ifdef CONFIG_IORT_TABLE void iort_table_detect(void); +u32 iort_msi_map_rid(struct device *dev, u32 req_id); +struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id); #else static inline void iort_table_detect(void) { } +static inline u32 iort_msi_map_rid(struct device *dev, u32 req_id) +{ return req_id; } +static inline struct irq_domain * +iort_get_device_domain(struct device *dev, u32 req_id) { return NULL; } #endif

#endif /* __IORT_H__ */

1.9.1