From mboxrd@z Thu Jan 1 00:00:00 1970 From: dennis.chen@arm.com (Dennis Chen) Date: Fri, 19 Aug 2016 11:39:13 +0800 Subject: [PATCH V8 1/8] ACPI: I/O Remapping Table (IORT) initial support In-Reply-To: <20160818111419.GB8982@red-moon> References: <1470909998-16710-1-git-send-email-tn@semihalf.com> <1470909998-16710-2-git-send-email-tn@semihalf.com> <20160818105549.GB20404@arm.com> <20160818111419.GB8982@red-moon> Message-ID: <20160819033911.GA4027@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Aug 18, 2016 at 12:14:20PM +0100, Lorenzo Pieralisi wrote: > 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. > Agree to check this in iort_scan_node(). Also, given some duplicate codes between iort_scan_node() and iort_smmu_init(), so maybe we can think about to refactor iort_match_callback() as the way to implement the function of iort_smmu_int(), thus we can call iort_node_match(ACPI_IORT_NODE_SMMU_V3)... Thanks, Dennis > > 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 > > > #endif > > > +#include > > > #include > > > #include > > > #include > > > @@ -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 > > > + * > > > + * 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 > > > + > > > +#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 at vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > >