From c25dc82899e67a32fdcfb20dd72a37fc236fde2e Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:07:30 -0600 Subject: [PATCH 1/7] PCI: Add DMA alias iterator In a mixed PCI/PCI-X/PCIe topology, bridges can take ownership of transactions, replacing the original requester ID with their own. Sometimes we just want to know the resulting device or resulting alias; other times we want each step in the chain. This iterator allows either usage. When an endpoint is connected via an unbroken chain of PCIe switches and root ports, it has no alias and its requester ID is visible to the root bus. When PCI/X get in the way, we pick up aliases for bridges. The reason why we potentially care about each step in the path is because of PCI-X. PCI-X has the concept of a requester ID, but bridges may or may not take ownership of various types of transactions. We therefore leave it to the consumer of this function to prune out what they don't care about rather than attempt to flatten the alias ourselves. Tested-by: George Spelvin Tested-by: Pat Erley Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/search.c | 70 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 4 +++ 2 files changed, 74 insertions(+) diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 4a1b972efe7f..5601cdb8bbb3 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -17,6 +17,76 @@ DECLARE_RWSEM(pci_bus_sem); EXPORT_SYMBOL_GPL(pci_bus_sem); +/* + * pci_for_each_dma_alias - Iterate over DMA aliases for a device + * @pdev: starting downstream device + * @fn: function to call for each alias + * @data: opaque data to pass to @fn + * + * Starting @pdev, walk up the bus calling @fn for each possible alias + * of @pdev at the root bus. + */ +int pci_for_each_dma_alias(struct pci_dev *pdev, + int (*fn)(struct pci_dev *pdev, + u16 alias, void *data), void *data) +{ + struct pci_bus *bus; + int ret; + + ret = fn(pdev, PCI_DEVID(pdev->bus->number, pdev->devfn), data); + if (ret) + return ret; + + for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) { + struct pci_dev *tmp; + + /* Skip virtual buses */ + if (!bus->self) + continue; + + tmp = bus->self; + + /* + * PCIe-to-PCI/X bridges alias transactions from downstream + * devices using the subordinate bus number (PCI Express to + * PCI/PCI-X Bridge Spec, rev 1.0, sec 2.3). For all cases + * where the upstream bus is PCI/X we alias to the bridge + * (there are various conditions in the previous reference + * where the bridge may take ownership of transactions, even + * when the secondary interface is PCI-X). + */ + if (pci_is_pcie(tmp)) { + switch (pci_pcie_type(tmp)) { + case PCI_EXP_TYPE_ROOT_PORT: + case PCI_EXP_TYPE_UPSTREAM: + case PCI_EXP_TYPE_DOWNSTREAM: + continue; + case PCI_EXP_TYPE_PCI_BRIDGE: + ret = fn(tmp, + PCI_DEVID(tmp->subordinate->number, + PCI_DEVFN(0, 0)), data); + if (ret) + return ret; + continue; + case PCI_EXP_TYPE_PCIE_BRIDGE: + ret = fn(tmp, + PCI_DEVID(tmp->bus->number, + tmp->devfn), data); + if (ret) + return ret; + continue; + } + } else { + ret = fn(tmp, PCI_DEVID(tmp->bus->number, tmp->devfn), + data); + if (ret) + return ret; + } + } + + return ret; +} + /* * find the upstream PCIe-to-PCI bridge of a PCI device * if the device is PCIE, return NULL diff --git a/include/linux/pci.h b/include/linux/pci.h index aab57b4abe7f..14b074bbc841 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1795,6 +1795,10 @@ static inline struct eeh_dev *pci_dev_to_eeh_dev(struct pci_dev *pdev) } #endif +int pci_for_each_dma_alias(struct pci_dev *pdev, + int (*fn)(struct pci_dev *pdev, + u16 alias, void *data), void *data); + /** * pci_find_upstream_pcie_bridge - find upstream PCIe-to-PCI bridge of a device * @pdev: the PCI device From 6b121592f8a3fd2bd0de128637b76a0d0864d993 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:07:36 -0600 Subject: [PATCH 2/7] PCI: Convert pci_dev_flags definitions to bit shifts Convert the pci_dev_flags definitions from decimal constants to bit shifts. We're only a few entries away from where using the decimal value becomes cumbersome. No functional change. Tested-by: George Spelvin Tested-by: Pat Erley Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- include/linux/pci.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/pci.h b/include/linux/pci.h index 14b074bbc841..545903df00dc 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -164,13 +164,13 @@ enum pci_dev_flags { /* INTX_DISABLE in PCI_COMMAND register disables MSI * generation too. */ - PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG = (__force pci_dev_flags_t) 1, + PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG = (__force pci_dev_flags_t) (1 << 0), /* Device configuration is irrevocably lost if disabled into D3 */ - PCI_DEV_FLAGS_NO_D3 = (__force pci_dev_flags_t) 2, + PCI_DEV_FLAGS_NO_D3 = (__force pci_dev_flags_t) (1 << 1), /* Provide indication device is assigned by a Virtual Machine Manager */ - PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) 4, + PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) (1 << 2), /* Flag for quirk use to store if quirk-specific ACS is enabled */ - PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) 8, + PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) (1 << 3), }; enum pci_irq_reroute_variant { From 31c2b8153c58f11ddb80dfd392c16f13c2d709c6 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:07:43 -0600 Subject: [PATCH 3/7] PCI: Add support for DMA alias quirks Some devices are broken and use a requester ID other than their physical devfn. Add a byte, using an existing gap in the pci_dev structure, to store an alternate "alias" devfn. A bit in the dev_flags tells us when this is valid. We then add the alias as one more step in the pci_for_each_dma_alias() iterator. Tested-by: George Spelvin Tested-by: Pat Erley Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/search.c | 11 +++++++++++ include/linux/pci.h | 3 +++ 2 files changed, 14 insertions(+) diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 5601cdb8bbb3..2c19f3f40621 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -37,6 +37,17 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, if (ret) return ret; + /* + * If the device is broken and uses an alias requester ID for + * DMA, iterate over that too. + */ + if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) { + ret = fn(pdev, PCI_DEVID(pdev->bus->number, + pdev->dma_alias_devfn), data); + if (ret) + return ret; + } + for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) { struct pci_dev *tmp; diff --git a/include/linux/pci.h b/include/linux/pci.h index 545903df00dc..9d4035c276f4 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -171,6 +171,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) (1 << 2), /* Flag for quirk use to store if quirk-specific ACS is enabled */ PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) (1 << 3), + /* Flag to indicate the device uses dma_alias_devfn */ + PCI_DEV_FLAGS_DMA_ALIAS_DEVFN = (__force pci_dev_flags_t) (1 << 4), }; enum pci_irq_reroute_variant { @@ -268,6 +270,7 @@ struct pci_dev { u8 rom_base_reg; /* which config register controls the ROM */ u8 pin; /* which interrupt pin this device uses */ u16 pcie_flags_reg; /* cached PCIe Capabilities Register */ + u8 dma_alias_devfn;/* devfn of DMA alias, if any */ struct pci_driver *driver; /* which driver has allocated this device */ u64 dma_mask; /* Mask of the bits of bus address this From ec637fb2d4f7a7167c323dc1d22837d1270a21bc Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:07:49 -0600 Subject: [PATCH 4/7] PCI: Add function 0 DMA alias quirk for Ricoh devices The existing quirk for these devices (pci_get_dma_source()) doesn't really solve the problem; re-implement it using the DMA alias iterator. We'll come back later and remove the existing quirk and dma_source interface. Note that device ID 0xe822 is typically function 0 and 0xe230 has been tested to not need the quirk and are therefore removed versus the equivalent dma_source quirk. If there exist in other configurations we can re-add them. Link: https://bugzilla.redhat.com/show_bug.cgi?id=605888 Tested-by: Pat Erley Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/quirks.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index e7292065a1b1..bc8ebd945612 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3333,6 +3333,22 @@ int pci_dev_specific_reset(struct pci_dev *dev, int probe) return -ENOTTY; } +static void quirk_dma_func0_alias(struct pci_dev *dev) +{ + if (PCI_FUNC(dev->devfn) != 0) { + dev->dma_alias_devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 0); + dev->dev_flags |= PCI_DEV_FLAGS_DMA_ALIAS_DEVFN; + } +} + +/* + * https://bugzilla.redhat.com/show_bug.cgi?id=605888 + * + * Some Ricoh devices use function 0 as the PCIe requester ID for DMA. + */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RICOH, 0xe832, quirk_dma_func0_alias); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RICOH, 0xe476, quirk_dma_func0_alias); + static struct pci_dev *pci_func_0_dma_source(struct pci_dev *dev) { if (!PCI_FUNC(dev->devfn)) From cc346a4714a59d08c118e8f33fd86692d3563133 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 28 May 2014 14:54:00 -0600 Subject: [PATCH 5/7] PCI: Add function 1 DMA alias quirk for Marvell devices MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Several Marvell devices and a JMicron device have a similar DMA requester ID problem to Ricoh, except they use function 1 as the PCIe requester ID. Add a quirk for these to populate the DMA alias with the correct devfn. Link: https://bugzilla.kernel.org/show_bug.cgi?id=42679 Tested-by: George Spelvin Tested-by: Andreas Schrägle Tested-by: Tobias N Tested-by: Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/quirks.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index bc8ebd945612..923689f554bb 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3349,6 +3349,42 @@ static void quirk_dma_func0_alias(struct pci_dev *dev) DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RICOH, 0xe832, quirk_dma_func0_alias); DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_RICOH, 0xe476, quirk_dma_func0_alias); +static void quirk_dma_func1_alias(struct pci_dev *dev) +{ + if (PCI_FUNC(dev->devfn) != 1) { + dev->dma_alias_devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 1); + dev->dev_flags |= PCI_DEV_FLAGS_DMA_ALIAS_DEVFN; + } +} + +/* + * Marvell 88SE9123 uses function 1 as the requester ID for DMA. In some + * SKUs function 1 is present and is a legacy IDE controller, in other + * SKUs this function is not present, making this a ghost requester. + * https://bugzilla.kernel.org/show_bug.cgi?id=42679 + */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9123, + quirk_dma_func1_alias); +/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c14 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9130, + quirk_dma_func1_alias); +/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c47 + c57 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9172, + quirk_dma_func1_alias); +/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c59 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x917a, + quirk_dma_func1_alias); +/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c46 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x91a0, + quirk_dma_func1_alias); +/* https://bugzilla.kernel.org/show_bug.cgi?id=42679#c49 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL_EXT, 0x9230, + quirk_dma_func1_alias); +/* https://bugs.gentoo.org/show_bug.cgi?id=497630 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_JMICRON, + PCI_DEVICE_ID_JMICRON_JMB388_ESD, + quirk_dma_func1_alias); + static struct pci_dev *pci_func_0_dma_source(struct pci_dev *dev) { if (!PCI_FUNC(dev->devfn)) From c8fe16e3f96a9bb95a10cedb19d2be2d2d580940 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 28 May 2014 14:57:02 -0600 Subject: [PATCH 6/7] PCI: Add support for PCIe-to-PCI bridge DMA alias quirks Several PCIe-to-PCI bridges fail to provide a PCIe capability, causing us to handle them as conventional PCI devices when they really use the requester ID of the secondary bus. We need to differentiate these from PCIe-to-PCI bridges that actually use the conventional PCI ID when a PCIe capability is not present, such as those found on the root complex of may Intel chipsets. Add a dev_flag bit to identify devices to be handled as standard PCIe-to-PCI bridges. Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/search.c | 10 ++++++++-- include/linux/pci.h | 2 ++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 2c19f3f40621..df38f73f091f 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -88,8 +88,14 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, continue; } } else { - ret = fn(tmp, PCI_DEVID(tmp->bus->number, tmp->devfn), - data); + if (tmp->dev_flags & PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS) + ret = fn(tmp, + PCI_DEVID(tmp->subordinate->number, + PCI_DEVFN(0, 0)), data); + else + ret = fn(tmp, + PCI_DEVID(tmp->bus->number, + tmp->devfn), data); if (ret) return ret; } diff --git a/include/linux/pci.h b/include/linux/pci.h index 9d4035c276f4..85ab35e974a9 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -173,6 +173,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) (1 << 3), /* Flag to indicate the device uses dma_alias_devfn */ PCI_DEV_FLAGS_DMA_ALIAS_DEVFN = (__force pci_dev_flags_t) (1 << 4), + /* Use a PCIe-to-PCI bridge alias even if !pci_is_pcie */ + PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS = (__force pci_dev_flags_t) (1 << 5), }; enum pci_irq_reroute_variant { From ebdb51eb7806df56221d4536a6a9702751d6df85 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:08:07 -0600 Subject: [PATCH 7/7] PCI: Add bridge DMA alias quirk for ASMedia and Tundra bridges The quirk is intended to be extremely generic, but we only apply it to known offending devices. Link: https://bugzilla.kernel.org/show_bug.cgi?id=44881 Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/quirks.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 923689f554bb..ab620aca632b 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3385,6 +3385,29 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB388_ESD, quirk_dma_func1_alias); +/* + * A few PCIe-to-PCI bridges fail to expose a PCIe capability, resulting in + * using the wrong DMA alias for the device. Some of these devices can be + * used as either forward or reverse bridges, so we need to test whether the + * device is operating in the correct mode. We could probably apply this + * quirk to PCI_ANY_ID, but for now we'll just use known offenders. The test + * is for a non-root, non-PCIe bridge where the upstream device is PCIe and + * is not a PCIe-to-PCI bridge, then @pdev is actually a PCIe-to-PCI bridge. + */ +static void quirk_use_pcie_bridge_dma_alias(struct pci_dev *pdev) +{ + if (!pci_is_root_bus(pdev->bus) && + pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE && + !pci_is_pcie(pdev) && pci_is_pcie(pdev->bus->self) && + pci_pcie_type(pdev->bus->self) != PCI_EXP_TYPE_PCI_BRIDGE) + pdev->dev_flags |= PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS; +} +/* ASM1083/1085, https://bugzilla.kernel.org/show_bug.cgi?id=44881#c46 */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ASMEDIA, 0x1080, + quirk_use_pcie_bridge_dma_alias); +/* Tundra 8113, https://bugzilla.kernel.org/show_bug.cgi?id=44881#c43 */ +DECLARE_PCI_FIXUP_HEADER(0x10e3, 0x8113, quirk_use_pcie_bridge_dma_alias); + static struct pci_dev *pci_func_0_dma_source(struct pci_dev *dev) { if (!PCI_FUNC(dev->devfn))