[PATCH V5 0/3] STA2X11: patches for pci bridge support

[PATCH V5 0/3] STA2X11: patches for pci bridge support

[Alessandro Rubini]

This is a repost of the patch set I sent on Mar 13th.
Patch 3 is modified to accound for a change in prototype for
the swiotlb alloc method.

Patch 3 is dependent on patch 1 and 2, which are unordered. The
big patch was picked up from V2 but without its dependencies.
It seems like the set can be accepted but was probably forgotten.

Other patches (for the sub-devices in this chip) are being worked on,
but they all depend on CONFIG_STA2X11, so I'd like these to be merged.
No problems have been reported on V4 and I actually expected Ingo to
pull them.

thanks
/alessandro


Summary:

Patch 1: no functional effect (it uses an existing "#ifdef CONFIG_X86_64"
in the 32-bit world, so it's not CONFIG_X86_64 but a new name)

Patch 2: no functional effect (it allows some inline functions to not be
inline where needed, with a new config symbol).

Patch 3: it's the real content.


History:

V5: rebased on next-20120403, fixed swiotlb change.

V4: rebased on next-20120309, no changes.

V3: rebased on next-20120221. Fixed patch 3 to match new DMA
prototypes. Renamed patch 3 as Ingo and Jesse merged it. Added both of
them to explicit Cc: list in the email set.

V2: rebased, minor and less-minor changes in patch 3/3.




Alessandro Rubini (3):
  x86: introduce CONFIG_X86_DEV_DMA_OPS
  x86: introduce CONFIG_X86_DMA_REMAP
  x86/PCI: initial support for sta2x11 I/O hub

 arch/x86/Kconfig                   |   34 +++-
 arch/x86/include/asm/device.h      |    4 +-
 arch/x86/include/asm/dma-mapping.h |    9 +-
 arch/x86/pci/Makefile              |    2 +
 arch/x86/pci/sta2x11-fixup.c       |  366 ++++++++++++++++++++++++++++++++++++
 5 files changed, 408 insertions(+), 7 deletions(-)
 create mode 100644 arch/x86/pci/sta2x11-fixup.c

-- 
1.7.7.2

[PATCH V5 1/3] x86: introduce CONFIG_X86_DEV_DMA_OPS

[Alessandro Rubini]

32-bit x86 systems may need their own DMA operations, so add
a new config option, which is turned on for 64-bit systems. This
patch has no functional effect but it paves the way for supporting
the STA2x11 I/O Hub and possibly other chips.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
---
 arch/x86/Kconfig                   |    5 +++++
 arch/x86/include/asm/device.h      |    4 ++--
 arch/x86/include/asm/dma-mapping.h |    2 +-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b3baf10..a3ce2e7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -12,6 +12,7 @@ config X86_32
 
 config X86_64
 	def_bool 64BIT
+	select X86_DEV_DMA_OPS
 
 ### Arch settings
 config X86
@@ -2249,6 +2250,10 @@ config HAVE_TEXT_POKE_SMP
 	bool
 	select STOP_MACHINE if SMP
 
+config X86_DEV_DMA_OPS
+	bool
+	depends on X86_64
+
 source "net/Kconfig"
 
 source "drivers/Kconfig"
diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index 63a2a03..93e1c55 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -5,8 +5,8 @@ struct dev_archdata {
 #ifdef CONFIG_ACPI
 	void	*acpi_handle;
 #endif
-#ifdef CONFIG_X86_64
-struct dma_map_ops *dma_ops;
+#ifdef CONFIG_X86_DEV_DMA_OPS
+	struct dma_map_ops *dma_ops;
 #endif
 #if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU)
 	void *iommu; /* hook for IOMMU specific extension */
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 4b4331d..09aa473 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -30,7 +30,7 @@ extern struct dma_map_ops *dma_ops;
 
 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 {
-#ifdef CONFIG_X86_32
+#ifndef CONFIG_X86_DEV_DMA_OPS
 	return dma_ops;
 #else
 	if (unlikely(!dev) || !dev->archdata.dma_ops)
-- 
1.7.7.2

[PATCH V5 2/3] x86: introduce CONFIG_X86_DMA_REMAP

[Alessandro Rubini]

The default functions phys_to_dma, dma_to_phys implement identity
mapping as fast inline functions.  Some systems, however, may need a
custom function to implement its own mapping between CPU addresses and
device addresses. This new configuration option allows the functions
to be external when needed (such as for the ConneXt device)

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
---
 arch/x86/Kconfig                   |    3 +++
 arch/x86/include/asm/dma-mapping.h |    7 +++++++
 2 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index a3ce2e7..46de79d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2254,6 +2254,9 @@ config X86_DEV_DMA_OPS
 	bool
 	depends on X86_64
 
+config X86_DMA_REMAP
+	bool
+
 source "net/Kconfig"
 
 source "drivers/Kconfig"
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 09aa473..61c0bd2 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -62,6 +62,12 @@ extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
 					dma_addr_t *dma_addr, gfp_t flag,
 					struct dma_attrs *attrs);
 
+#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
+extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
+extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
+extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
+#else
+
 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	if (!dev->dma_mask)
@@ -79,6 +85,7 @@ static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
 	return daddr;
 }
+#endif /* CONFIG_X86_DMA_REMAP */
 
 static inline void
 dma_cache_sync(struct device *dev, void *vaddr, size_t size,
-- 
1.7.7.2

[PATCH V5 3/3] x86/PCI: initial support for sta2x11 I/O hub

[Alessandro Rubini]

The "ConneXt" sta2x11 I/O Hub is a bridge from PCIe to AMBA, and is
used as main chipset in some Atom boards.  The set of peripherals it
exports live in an AMBA bus internal to the chip, so a custom
remapping of addresses is needed. This is implemented by fixup calls
for the PCI deivices, based on CONFIG_X86_DEV_DMA_OPS and
CONFIG_X86_DMA_REMAP .

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
---
 arch/x86/Kconfig             |   28 +++-
 arch/x86/pci/Makefile        |    2 +
 arch/x86/pci/sta2x11-fixup.c |  366 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 391 insertions(+), 5 deletions(-)
 create mode 100644 arch/x86/pci/sta2x11-fixup.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 46de79d..16012ba 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -332,6 +332,7 @@ config X86_EXTENDED_PLATFORM
 		NUMAQ (IBM/Sequent)
 		RDC R-321x SoC
 		SGI 320/540 (Visual Workstation)
+		STA2X11-based (e.g. Northville)
 		Summit/EXA (IBM x440)
 		Unisys ES7000 IA32 series
 		Moorestown MID devices
@@ -464,10 +465,10 @@ config X86_32_NON_STANDARD
 	depends on X86_32 && SMP
 	depends on X86_EXTENDED_PLATFORM
 	---help---
-	  This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
-	  subarchitectures.  It is intended for a generic binary kernel.
-	  if you select them all, kernel will probe it one by one. and will
-	  fallback to default.
+	  This option compiles in the NUMAQ, Summit, bigsmp, ES7000, 
+	  STA2X11, default subarchitectures.  It is intended for a generic
+	  binary kernel. If you select them all, kernel will probe it
+	  one by one and will fallback to default.
 
 # Alphabetically sorted list of Non standard 32 bit platforms
 
@@ -507,6 +508,22 @@ config X86_VISWS
 	  A kernel compiled for the Visual Workstation will run on general
 	  PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 
+config STA2X11
+	bool "STA2X11 Companion Chip Support"
+	depends on X86_32_NON_STANDARD && PCI
+	select X86_DEV_DMA_OPS
+	select X86_DMA_REMAP
+	select SWIOTLB
+	select MFD_STA2X11
+	select ARCH_REQUIRE_GPIOLIB
+	default n
+	---help---
+	  This adds support for boards based on the STA2X11 IO-Hub,
+	  a.k.a. "ConneXt". The chip is used in place of the standard
+	  PC chipset, so all "standard" peripherals are missing. If this
+	  option is selected the kernel will still be able to boot on
+	  standard PC machines.
+
 config X86_SUMMIT
 	bool "Summit/EXA (IBM x440)"
 	depends on X86_32_NON_STANDARD
@@ -2252,10 +2269,11 @@ config HAVE_TEXT_POKE_SMP
 
 config X86_DEV_DMA_OPS
 	bool
-	depends on X86_64
+	depends on X86_64 || STA2X11
 
 config X86_DMA_REMAP
 	bool
+	depends on STA2X11
 
 source "net/Kconfig"
 
diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index e76e18c..3af5a1e 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -11,6 +11,8 @@ obj-$(CONFIG_X86_INTEL_CE)      += ce4100.o
 obj-$(CONFIG_ACPI)		+= acpi.o
 obj-y				+= legacy.o irq.o
 
+obj-$(CONFIG_STA2X11)           += sta2x11-fixup.o
+
 obj-$(CONFIG_X86_VISWS)		+= visws.o
 
 obj-$(CONFIG_X86_NUMAQ)		+= numaq_32.o
diff --git a/arch/x86/pci/sta2x11-fixup.c b/arch/x86/pci/sta2x11-fixup.c
new file mode 100644
index 0000000..9d8a509
--- /dev/null
+++ b/arch/x86/pci/sta2x11-fixup.c
@@ -0,0 +1,366 @@
+/*
+ * arch/x86/pci/sta2x11-fixup.c
+ * glue code for lib/swiotlb.c and DMA translation between STA2x11
+ * AMBA memory mapping and the X86 memory mapping
+ *
+ * ST Microelectronics ConneXt (STA2X11/STA2X10)
+ *
+ * Copyright (c) 2010-2011 Wind River Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/export.h>
+#include <linux/list.h>
+
+#define STA2X11_SWIOTLB_SIZE (4*1024*1024)
+extern int swiotlb_late_init_with_default_size(size_t default_size);
+
+/*
+ * We build a list of bus numbers that are under the ConneXt. The
+ * main bridge hosts 4 busses, which are the 4 endpoints, in order.
+ */
+#define STA2X11_NR_EP		4	/* 0..3 included */
+#define STA2X11_NR_FUNCS	8	/* 0..7 included */
+#define STA2X11_AMBA_SIZE	(512 << 20)
+
+struct sta2x11_ahb_regs { /* saved during suspend */
+	u32 base, pexlbase, pexhbase, crw;
+};
+
+struct sta2x11_mapping {
+	u32 amba_base;
+	int is_suspended;
+	struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS];
+};
+
+struct sta2x11_instance {
+	struct list_head list;
+	int bus0;
+	struct sta2x11_mapping map[STA2X11_NR_EP];
+};
+
+static LIST_HEAD(sta2x11_instance_list);
+
+/* At probe time, record new instances of this bridge (likely one only) */
+static void sta2x11_new_instance(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+
+	instance = kzalloc(sizeof(*instance), GFP_ATOMIC);
+	if (!instance)
+		return;
+	/* This has a subordinate bridge, with 4 more-subordinate ones */
+	instance->bus0 = pdev->subordinate->number + 1;
+
+	if (list_empty(&sta2x11_instance_list)) {
+		int size = STA2X11_SWIOTLB_SIZE;
+		/* First instance: register your own swiotlb area */
+		dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size);
+		if (swiotlb_late_init_with_default_size(size))
+			dev_emerg(&pdev->dev, "init swiotlb failed\n");
+	}
+	list_add(&instance->list, &sta2x11_instance_list);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance);
+
+/*
+ * Utility functions used in this file from below
+ */
+static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+	int ep;
+
+	list_for_each_entry(instance, &sta2x11_instance_list, list) {
+		ep = pdev->bus->number - instance->bus0;
+		if (ep >= 0 && ep < STA2X11_NR_EP)
+			return instance;
+	}
+	return NULL;
+}
+
+static int sta2x11_pdev_to_ep(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+
+	instance = sta2x11_pdev_to_instance(pdev);
+	if (!instance)
+		return -1;
+
+	return pdev->bus->number - instance->bus0;
+}
+
+static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+	int ep;
+
+	instance = sta2x11_pdev_to_instance(pdev);
+	if (!instance)
+		return NULL;
+	ep = sta2x11_pdev_to_ep(pdev);
+	return instance->map + ep;
+}
+
+/* This is exported, as some devices need to access the MFD registers */
+struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev)
+{
+	return sta2x11_pdev_to_instance(pdev);
+}
+EXPORT_SYMBOL(sta2x11_get_instance);
+
+
+/**
+ * p2a - Translate physical address to STA2x11 AMBA address,
+ *       used for DMA transfers to STA2x11
+ * @p: Physical address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map;
+	dma_addr_t a;
+
+	map = sta2x11_pdev_to_mapping(pdev);
+	a = p + map->amba_base;
+	return a;
+}
+
+/**
+ * a2p - Translate STA2x11 AMBA address to physical address
+ *       used for DMA transfers from STA2x11
+ * @a: STA2x11 AMBA address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map;
+	dma_addr_t p;
+
+	map = sta2x11_pdev_to_mapping(pdev);
+	p = a - map->amba_base;
+	return p;
+}
+
+/**
+ * sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers
+ *     returns virtual address. This is the only "special" function here.
+ * @dev: PCI device
+ * @size: Size of the buffer
+ * @dma_handle: DMA address
+ * @flags: memory flags
+ */
+static void *sta2x11_swiotlb_alloc_coherent(struct device *dev,
+					    size_t size,
+					    dma_addr_t *dma_handle,
+					    gfp_t flags,
+					    struct dma_attrs *attrs)
+{
+	void *vaddr;
+
+	vaddr = dma_generic_alloc_coherent(dev, size, dma_handle, flags, attrs);
+	if (!vaddr)
+		vaddr = swiotlb_alloc_coherent(dev, size, dma_handle, flags);
+	*dma_handle = p2a(*dma_handle, to_pci_dev(dev));
+	return vaddr;
+}
+
+/* We have our own dma_ops: the same as swiotlb but from alloc (above) */
+static struct dma_map_ops sta2x11_dma_ops = {
+	.alloc = sta2x11_swiotlb_alloc_coherent,
+	.free = swiotlb_free_coherent,
+	.map_page = swiotlb_map_page,
+	.unmap_page = swiotlb_unmap_page,
+	.map_sg = swiotlb_map_sg_attrs,
+	.unmap_sg = swiotlb_unmap_sg_attrs,
+	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
+	.sync_single_for_device = swiotlb_sync_single_for_device,
+	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
+	.sync_sg_for_device = swiotlb_sync_sg_for_device,
+	.mapping_error = swiotlb_dma_mapping_error,
+	.dma_supported = NULL, /* FIXME: we should use this instead! */
+};
+
+/* At setup time, we use our own ops if the device is a ConneXt one */
+static void sta2x11_setup_pdev(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
+
+	if (!instance) /* either a sta2x11 bridge or another ST device */
+		return;
+	pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+	pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+	pdev->dev.archdata.dma_ops = &sta2x11_dma_ops;
+
+	/* We must enable all devices as master, for audio DMA to work */
+	pci_set_master(pdev);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev);
+
+/*
+ * The following three functions are exported (used in swiotlb: FIXME)
+ */
+/**
+ * dma_capable - Check if device can manage DMA transfers (FIXME: kill it)
+ * @dev: device for a PCI device
+ * @addr: DMA address
+ * @size: DMA size
+ */
+bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+{
+	struct sta2x11_mapping *map;
+
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops) {
+		if (!dev->dma_mask)
+			return false;
+		return addr + size - 1 <= *dev->dma_mask;
+	}
+
+	map = sta2x11_pdev_to_mapping(to_pci_dev(dev));
+
+	if (!map || (addr < map->amba_base))
+		return false;
+	if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) {
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
+ * @dev: device for a PCI device
+ * @paddr: Physical address
+ */
+dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+		return paddr;
+	return p2a(paddr, to_pci_dev(dev));
+}
+
+/**
+ * dma_to_phys - Return the physical address used for this STA2x11 DMA address
+ * @dev: device for a PCI device
+ * @daddr: STA2x11 AMBA DMA address
+ */
+phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+		return daddr;
+	return a2p(daddr, to_pci_dev(dev));
+}
+
+
+/*
+ * At boot we must set up the mappings for the pcie-to-amba bridge.
+ * It involves device access, and the same happens at suspend/resume time
+ */
+
+#define AHB_MAPB		0xCA4
+#define AHB_CRW(i)		(AHB_MAPB + 0  + (i) * 0x10)
+#define AHB_CRW_SZMASK			0xfffffc00UL
+#define AHB_CRW_ENABLE			(1 << 0)
+#define AHB_CRW_WTYPE_MEM		(2 << 1)
+#define AHB_CRW_ROE			(1UL << 3)	/* Relax Order Ena */
+#define AHB_CRW_NSE			(1UL << 4)	/* No Snoop Enable */
+#define AHB_BASE(i)		(AHB_MAPB + 4  + (i) * 0x10)
+#define AHB_PEXLBASE(i)		(AHB_MAPB + 8  + (i) * 0x10)
+#define AHB_PEXHBASE(i)		(AHB_MAPB + 12 + (i) * 0x10)
+
+/* At probe time, enable mapping for each endpoint, using the pdev */
+static void sta2x11_map_ep(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+	pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base);
+
+	/* Configure AHB mapping */
+	pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0);
+	pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0);
+	pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE |
+			       AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE);
+
+	/* Disable all the other windows */
+	for (i = 1; i < STA2X11_NR_FUNCS; i++)
+		pci_write_config_dword(pdev, AHB_CRW(i), 0);
+
+	dev_info(&pdev->dev,
+		 "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n",
+		 sta2x11_pdev_to_ep(pdev),  map->amba_base,
+		 map->amba_base + STA2X11_AMBA_SIZE - 1);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep);
+
+#ifdef CONFIG_PM /* Some register values must be saved and restored */
+
+static void suspend_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+
+	if (map->is_suspended)
+		return;
+	map->is_suspended = 1;
+
+	/* Save all window configs */
+	for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+		struct sta2x11_ahb_regs *regs = map->regs + i;
+
+		pci_read_config_dword(pdev, AHB_BASE(i), &regs->base);
+		pci_read_config_dword(pdev, AHB_PEXLBASE(i), &regs->pexlbase);
+		pci_read_config_dword(pdev, AHB_PEXHBASE(i), &regs->pexhbase);
+		pci_read_config_dword(pdev, AHB_CRW(i), &regs->crw);
+	}
+}
+DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping);
+
+static void resume_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+
+
+	if (!map->is_suspended)
+		goto out;
+	map->is_suspended = 0;
+
+	/* Restore all window configs */
+	for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+		struct sta2x11_ahb_regs *regs = map->regs + i;
+
+		pci_write_config_dword(pdev, AHB_BASE(i), regs->base);
+		pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase);
+		pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase);
+		pci_write_config_dword(pdev, AHB_CRW(i), regs->crw);
+	}
+out:
+	pci_set_master(pdev); /* Like at boot, enable master on all devices */
+}
+DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping);
+
+#endif /* CONFIG_PM */
-- 
1.7.7.2

[tip:x86/platform] x86-32: Introduce CONFIG_X86_DEV_DMA_OPS

[tip-bot for Alessandro Rubini]

Commit-ID:  4692d77fc3c8978a36406a3cf9e8b899f86f68f1
Gitweb:     http://git.kernel.org/tip/4692d77fc3c8978a36406a3cf9e8b899f86f68f1
Author:     Alessandro Rubini <rubini@gnudd.com>
AuthorDate: Wed, 4 Apr 2012 19:39:58 +0200
Committer:  H. Peter Anvin <hpa@zytor.com>
CommitDate: Thu, 12 Apr 2012 11:09:56 -0700

x86-32: Introduce CONFIG_X86_DEV_DMA_OPS

32-bit x86 systems may need their own DMA operations, so add
a new config option, which is turned on for 64-bit systems. This
patch has no functional effect but it paves the way for supporting
the STA2x11 I/O Hub and possibly other chips.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Link: http://lkml.kernel.org/r/f79fcc1a2e17ef942e1b798b92aac43a80202532.1333560789.git.rubini@gnudd.com
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 arch/x86/Kconfig                   |    5 +++++
 arch/x86/include/asm/device.h      |    4 ++--
 arch/x86/include/asm/dma-mapping.h |    2 +-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1d14cc6..07b412a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -12,6 +12,7 @@ config X86_32
 
 config X86_64
 	def_bool 64BIT
+	select X86_DEV_DMA_OPS
 
 ### Arch settings
 config X86
@@ -2215,6 +2216,10 @@ config HAVE_TEXT_POKE_SMP
 	bool
 	select STOP_MACHINE if SMP
 
+config X86_DEV_DMA_OPS
+	bool
+	depends on X86_64
+
 source "net/Kconfig"
 
 source "drivers/Kconfig"
diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index 63a2a03..93e1c55 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -5,8 +5,8 @@ struct dev_archdata {
 #ifdef CONFIG_ACPI
 	void	*acpi_handle;
 #endif
-#ifdef CONFIG_X86_64
-struct dma_map_ops *dma_ops;
+#ifdef CONFIG_X86_DEV_DMA_OPS
+	struct dma_map_ops *dma_ops;
 #endif
 #if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU)
 	void *iommu; /* hook for IOMMU specific extension */
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 4b4331d..09aa473 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -30,7 +30,7 @@ extern struct dma_map_ops *dma_ops;
 
 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 {
-#ifdef CONFIG_X86_32
+#ifndef CONFIG_X86_DEV_DMA_OPS
 	return dma_ops;
 #else
 	if (unlikely(!dev) || !dev->archdata.dma_ops)

[tip:x86/platform] x86: Introduce CONFIG_X86_DMA_REMAP

[tip-bot for Alessandro Rubini]

Commit-ID:  f7219a5300ba753b0c762d631763bd878b8bb00c
Gitweb:     http://git.kernel.org/tip/f7219a5300ba753b0c762d631763bd878b8bb00c
Author:     Alessandro Rubini <rubini@gnudd.com>
AuthorDate: Wed, 4 Apr 2012 19:40:10 +0200
Committer:  H. Peter Anvin <hpa@zytor.com>
CommitDate: Thu, 12 Apr 2012 11:10:18 -0700

x86: Introduce CONFIG_X86_DMA_REMAP

The default functions phys_to_dma, dma_to_phys implement identity
mapping as fast inline functions.  Some systems, however, may need a
custom function to implement its own mapping between CPU addresses and
device addresses. This new configuration option allows the functions
to be external when needed (such as for the ConneXt device)

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Link: http://lkml.kernel.org/r/6e4329b772df675f1c442f68e59e844e4dd8c965.1333560789.git.rubini@gnudd.com
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 arch/x86/Kconfig                   |    3 +++
 arch/x86/include/asm/dma-mapping.h |    7 +++++++
 2 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 07b412a..95ca560 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2220,6 +2220,9 @@ config X86_DEV_DMA_OPS
 	bool
 	depends on X86_64
 
+config X86_DMA_REMAP
+	bool
+
 source "net/Kconfig"
 
 source "drivers/Kconfig"
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 09aa473..61c0bd2 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -62,6 +62,12 @@ extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
 					dma_addr_t *dma_addr, gfp_t flag,
 					struct dma_attrs *attrs);
 
+#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
+extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
+extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
+extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
+#else
+
 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	if (!dev->dma_mask)
@@ -79,6 +85,7 @@ static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
 	return daddr;
 }
+#endif /* CONFIG_X86_DMA_REMAP */
 
 static inline void
 dma_cache_sync(struct device *dev, void *vaddr, size_t size,

[tip:x86/platform] x86, platform: Initial support for sta2x11 I/ O hub

[tip-bot for Alessandro Rubini]

Commit-ID:  83125a3a189ec34fb22a04e8efad69ae6d52674a
Gitweb:     http://git.kernel.org/tip/83125a3a189ec34fb22a04e8efad69ae6d52674a
Author:     Alessandro Rubini <rubini@gnudd.com>
AuthorDate: Wed, 4 Apr 2012 19:40:21 +0200
Committer:  H. Peter Anvin <hpa@zytor.com>
CommitDate: Thu, 12 Apr 2012 11:10:30 -0700

x86, platform: Initial support for sta2x11 I/O hub

The "ConneXt" sta2x11 I/O Hub is a bridge from PCIe to AMBA, and is
used as main chipset in some Atom boards.  The set of peripherals it
exports live in an AMBA bus internal to the chip, so a custom
remapping of addresses is needed. This is implemented by fixup calls
for the PCI deivices, based on CONFIG_X86_DEV_DMA_OPS and
CONFIG_X86_DMA_REMAP .

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Link: http://lkml.kernel.org/r/ddca670ca8180e52d49b3fe642742ddd23ab2cb2.1333560789.git.rubini@gnudd.com
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 arch/x86/Kconfig             |   28 +++-
 arch/x86/pci/Makefile        |    2 +
 arch/x86/pci/sta2x11-fixup.c |  366 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 391 insertions(+), 5 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 95ca560..f9ed801 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -329,6 +329,7 @@ config X86_EXTENDED_PLATFORM
 		NUMAQ (IBM/Sequent)
 		RDC R-321x SoC
 		SGI 320/540 (Visual Workstation)
+		STA2X11-based (e.g. Northville)
 		Summit/EXA (IBM x440)
 		Unisys ES7000 IA32 series
 		Moorestown MID devices
@@ -461,10 +462,10 @@ config X86_32_NON_STANDARD
 	depends on X86_32 && SMP
 	depends on X86_EXTENDED_PLATFORM
 	---help---
-	  This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
-	  subarchitectures.  It is intended for a generic binary kernel.
-	  if you select them all, kernel will probe it one by one. and will
-	  fallback to default.
+	  This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
+	  STA2X11, default subarchitectures.  It is intended for a generic
+	  binary kernel. If you select them all, kernel will probe it
+	  one by one and will fallback to default.
 
 # Alphabetically sorted list of Non standard 32 bit platforms
 
@@ -504,6 +505,22 @@ config X86_VISWS
 	  A kernel compiled for the Visual Workstation will run on general
 	  PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 
+config STA2X11
+	bool "STA2X11 Companion Chip Support"
+	depends on X86_32_NON_STANDARD && PCI
+	select X86_DEV_DMA_OPS
+	select X86_DMA_REMAP
+	select SWIOTLB
+	select MFD_STA2X11
+	select ARCH_REQUIRE_GPIOLIB
+	default n
+	---help---
+	  This adds support for boards based on the STA2X11 IO-Hub,
+	  a.k.a. "ConneXt". The chip is used in place of the standard
+	  PC chipset, so all "standard" peripherals are missing. If this
+	  option is selected the kernel will still be able to boot on
+	  standard PC machines.
+
 config X86_SUMMIT
 	bool "Summit/EXA (IBM x440)"
 	depends on X86_32_NON_STANDARD
@@ -2218,10 +2235,11 @@ config HAVE_TEXT_POKE_SMP
 
 config X86_DEV_DMA_OPS
 	bool
-	depends on X86_64
+	depends on X86_64 || STA2X11
 
 config X86_DMA_REMAP
 	bool
+	depends on STA2X11
 
 source "net/Kconfig"
 
diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index e76e18c..3af5a1e 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -11,6 +11,8 @@ obj-$(CONFIG_X86_INTEL_CE)      += ce4100.o
 obj-$(CONFIG_ACPI)		+= acpi.o
 obj-y				+= legacy.o irq.o
 
+obj-$(CONFIG_STA2X11)           += sta2x11-fixup.o
+
 obj-$(CONFIG_X86_VISWS)		+= visws.o
 
 obj-$(CONFIG_X86_NUMAQ)		+= numaq_32.o
diff --git a/arch/x86/pci/sta2x11-fixup.c b/arch/x86/pci/sta2x11-fixup.c
new file mode 100644
index 0000000..9d8a509
--- /dev/null
+++ b/arch/x86/pci/sta2x11-fixup.c
@@ -0,0 +1,366 @@
+/*
+ * arch/x86/pci/sta2x11-fixup.c
+ * glue code for lib/swiotlb.c and DMA translation between STA2x11
+ * AMBA memory mapping and the X86 memory mapping
+ *
+ * ST Microelectronics ConneXt (STA2X11/STA2X10)
+ *
+ * Copyright (c) 2010-2011 Wind River Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/export.h>
+#include <linux/list.h>
+
+#define STA2X11_SWIOTLB_SIZE (4*1024*1024)
+extern int swiotlb_late_init_with_default_size(size_t default_size);
+
+/*
+ * We build a list of bus numbers that are under the ConneXt. The
+ * main bridge hosts 4 busses, which are the 4 endpoints, in order.
+ */
+#define STA2X11_NR_EP		4	/* 0..3 included */
+#define STA2X11_NR_FUNCS	8	/* 0..7 included */
+#define STA2X11_AMBA_SIZE	(512 << 20)
+
+struct sta2x11_ahb_regs { /* saved during suspend */
+	u32 base, pexlbase, pexhbase, crw;
+};
+
+struct sta2x11_mapping {
+	u32 amba_base;
+	int is_suspended;
+	struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS];
+};
+
+struct sta2x11_instance {
+	struct list_head list;
+	int bus0;
+	struct sta2x11_mapping map[STA2X11_NR_EP];
+};
+
+static LIST_HEAD(sta2x11_instance_list);
+
+/* At probe time, record new instances of this bridge (likely one only) */
+static void sta2x11_new_instance(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+
+	instance = kzalloc(sizeof(*instance), GFP_ATOMIC);
+	if (!instance)
+		return;
+	/* This has a subordinate bridge, with 4 more-subordinate ones */
+	instance->bus0 = pdev->subordinate->number + 1;
+
+	if (list_empty(&sta2x11_instance_list)) {
+		int size = STA2X11_SWIOTLB_SIZE;
+		/* First instance: register your own swiotlb area */
+		dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size);
+		if (swiotlb_late_init_with_default_size(size))
+			dev_emerg(&pdev->dev, "init swiotlb failed\n");
+	}
+	list_add(&instance->list, &sta2x11_instance_list);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance);
+
+/*
+ * Utility functions used in this file from below
+ */
+static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+	int ep;
+
+	list_for_each_entry(instance, &sta2x11_instance_list, list) {
+		ep = pdev->bus->number - instance->bus0;
+		if (ep >= 0 && ep < STA2X11_NR_EP)
+			return instance;
+	}
+	return NULL;
+}
+
+static int sta2x11_pdev_to_ep(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+
+	instance = sta2x11_pdev_to_instance(pdev);
+	if (!instance)
+		return -1;
+
+	return pdev->bus->number - instance->bus0;
+}
+
+static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+	int ep;
+
+	instance = sta2x11_pdev_to_instance(pdev);
+	if (!instance)
+		return NULL;
+	ep = sta2x11_pdev_to_ep(pdev);
+	return instance->map + ep;
+}
+
+/* This is exported, as some devices need to access the MFD registers */
+struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev)
+{
+	return sta2x11_pdev_to_instance(pdev);
+}
+EXPORT_SYMBOL(sta2x11_get_instance);
+
+
+/**
+ * p2a - Translate physical address to STA2x11 AMBA address,
+ *       used for DMA transfers to STA2x11
+ * @p: Physical address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map;
+	dma_addr_t a;
+
+	map = sta2x11_pdev_to_mapping(pdev);
+	a = p + map->amba_base;
+	return a;
+}
+
+/**
+ * a2p - Translate STA2x11 AMBA address to physical address
+ *       used for DMA transfers from STA2x11
+ * @a: STA2x11 AMBA address
+ * @pdev: PCI device (must be hosted within the connext)
+ */
+static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map;
+	dma_addr_t p;
+
+	map = sta2x11_pdev_to_mapping(pdev);
+	p = a - map->amba_base;
+	return p;
+}
+
+/**
+ * sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers
+ *     returns virtual address. This is the only "special" function here.
+ * @dev: PCI device
+ * @size: Size of the buffer
+ * @dma_handle: DMA address
+ * @flags: memory flags
+ */
+static void *sta2x11_swiotlb_alloc_coherent(struct device *dev,
+					    size_t size,
+					    dma_addr_t *dma_handle,
+					    gfp_t flags,
+					    struct dma_attrs *attrs)
+{
+	void *vaddr;
+
+	vaddr = dma_generic_alloc_coherent(dev, size, dma_handle, flags, attrs);
+	if (!vaddr)
+		vaddr = swiotlb_alloc_coherent(dev, size, dma_handle, flags);
+	*dma_handle = p2a(*dma_handle, to_pci_dev(dev));
+	return vaddr;
+}
+
+/* We have our own dma_ops: the same as swiotlb but from alloc (above) */
+static struct dma_map_ops sta2x11_dma_ops = {
+	.alloc = sta2x11_swiotlb_alloc_coherent,
+	.free = swiotlb_free_coherent,
+	.map_page = swiotlb_map_page,
+	.unmap_page = swiotlb_unmap_page,
+	.map_sg = swiotlb_map_sg_attrs,
+	.unmap_sg = swiotlb_unmap_sg_attrs,
+	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
+	.sync_single_for_device = swiotlb_sync_single_for_device,
+	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
+	.sync_sg_for_device = swiotlb_sync_sg_for_device,
+	.mapping_error = swiotlb_dma_mapping_error,
+	.dma_supported = NULL, /* FIXME: we should use this instead! */
+};
+
+/* At setup time, we use our own ops if the device is a ConneXt one */
+static void sta2x11_setup_pdev(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
+
+	if (!instance) /* either a sta2x11 bridge or another ST device */
+		return;
+	pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+	pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
+	pdev->dev.archdata.dma_ops = &sta2x11_dma_ops;
+
+	/* We must enable all devices as master, for audio DMA to work */
+	pci_set_master(pdev);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev);
+
+/*
+ * The following three functions are exported (used in swiotlb: FIXME)
+ */
+/**
+ * dma_capable - Check if device can manage DMA transfers (FIXME: kill it)
+ * @dev: device for a PCI device
+ * @addr: DMA address
+ * @size: DMA size
+ */
+bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+{
+	struct sta2x11_mapping *map;
+
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops) {
+		if (!dev->dma_mask)
+			return false;
+		return addr + size - 1 <= *dev->dma_mask;
+	}
+
+	map = sta2x11_pdev_to_mapping(to_pci_dev(dev));
+
+	if (!map || (addr < map->amba_base))
+		return false;
+	if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) {
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
+ * @dev: device for a PCI device
+ * @paddr: Physical address
+ */
+dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+		return paddr;
+	return p2a(paddr, to_pci_dev(dev));
+}
+
+/**
+ * dma_to_phys - Return the physical address used for this STA2x11 DMA address
+ * @dev: device for a PCI device
+ * @daddr: STA2x11 AMBA DMA address
+ */
+phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+	if (dev->archdata.dma_ops != &sta2x11_dma_ops)
+		return daddr;
+	return a2p(daddr, to_pci_dev(dev));
+}
+
+
+/*
+ * At boot we must set up the mappings for the pcie-to-amba bridge.
+ * It involves device access, and the same happens at suspend/resume time
+ */
+
+#define AHB_MAPB		0xCA4
+#define AHB_CRW(i)		(AHB_MAPB + 0  + (i) * 0x10)
+#define AHB_CRW_SZMASK			0xfffffc00UL
+#define AHB_CRW_ENABLE			(1 << 0)
+#define AHB_CRW_WTYPE_MEM		(2 << 1)
+#define AHB_CRW_ROE			(1UL << 3)	/* Relax Order Ena */
+#define AHB_CRW_NSE			(1UL << 4)	/* No Snoop Enable */
+#define AHB_BASE(i)		(AHB_MAPB + 4  + (i) * 0x10)
+#define AHB_PEXLBASE(i)		(AHB_MAPB + 8  + (i) * 0x10)
+#define AHB_PEXHBASE(i)		(AHB_MAPB + 12 + (i) * 0x10)
+
+/* At probe time, enable mapping for each endpoint, using the pdev */
+static void sta2x11_map_ep(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+	pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base);
+
+	/* Configure AHB mapping */
+	pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0);
+	pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0);
+	pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE |
+			       AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE);
+
+	/* Disable all the other windows */
+	for (i = 1; i < STA2X11_NR_FUNCS; i++)
+		pci_write_config_dword(pdev, AHB_CRW(i), 0);
+
+	dev_info(&pdev->dev,
+		 "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n",
+		 sta2x11_pdev_to_ep(pdev),  map->amba_base,
+		 map->amba_base + STA2X11_AMBA_SIZE - 1);
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep);
+
+#ifdef CONFIG_PM /* Some register values must be saved and restored */
+
+static void suspend_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+
+	if (map->is_suspended)
+		return;
+	map->is_suspended = 1;
+
+	/* Save all window configs */
+	for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+		struct sta2x11_ahb_regs *regs = map->regs + i;
+
+		pci_read_config_dword(pdev, AHB_BASE(i), &regs->base);
+		pci_read_config_dword(pdev, AHB_PEXLBASE(i), &regs->pexlbase);
+		pci_read_config_dword(pdev, AHB_PEXHBASE(i), &regs->pexhbase);
+		pci_read_config_dword(pdev, AHB_CRW(i), &regs->crw);
+	}
+}
+DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping);
+
+static void resume_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	int i;
+
+	if (!map)
+		return;
+
+
+	if (!map->is_suspended)
+		goto out;
+	map->is_suspended = 0;
+
+	/* Restore all window configs */
+	for (i = 0; i < STA2X11_NR_FUNCS; i++) {
+		struct sta2x11_ahb_regs *regs = map->regs + i;
+
+		pci_write_config_dword(pdev, AHB_BASE(i), regs->base);
+		pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase);
+		pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase);
+		pci_write_config_dword(pdev, AHB_CRW(i), regs->crw);
+	}
+out:
+	pci_set_master(pdev); /* Like at boot, enable master on all devices */
+}
+DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping);
+
+#endif /* CONFIG_PM */