#include "pci.h"
/*
- * PCI iomap devres
+ * On the state of PCI's devres implementation:
+ *
+ * The older devres API for PCI has two significant problems:
+ *
+ * 1. It is very strongly tied to the statically allocated mapping table in
+ * struct pcim_iomap_devres below. This is mostly solved in the sense of the
+ * pcim_ functions in this file providing things like ranged mapping by
+ * bypassing this table, whereas the functions that were present in the old
+ * API still enter the mapping addresses into the table for users of the old
+ * API.
+ *
+ * 2. The region-request-functions in pci.c do become managed IF the device has
+ * been enabled with pcim_enable_device() instead of pci_enable_device().
+ * This resulted in the API becoming inconsistent: Some functions have an
+ * obviously managed counter-part (e.g., pci_iomap() <-> pcim_iomap()),
+ * whereas some don't and are never managed, while others don't and are
+ * _sometimes_ managed (e.g. pci_request_region()).
+ *
+ * Consequently, in the new API, region requests performed by the pcim_
+ * functions are automatically cleaned up through the devres callback
+ * pcim_addr_resource_release(), while requests performed by
+ * pcim_enable_device() + pci_*region*() are automatically cleaned up
+ * through the for-loop in pcim_release().
+ *
+ * TODO 1:
+ * Remove the legacy table entirely once all calls to pcim_iomap_table() in
+ * the kernel have been removed.
+ *
+ * TODO 2:
+ * Port everyone calling pcim_enable_device() + pci_*region*() to using the
+ * pcim_ functions. Then, remove all devres functionality from pci_*region*()
+ * functions and remove the associated cleanups described above in point #2.
*/
-#define PCIM_IOMAP_MAX PCI_STD_NUM_BARS
+/*
+ * Legacy struct storing addresses to whole mapped BARs.
+ */
struct pcim_iomap_devres {
- void __iomem *table[PCIM_IOMAP_MAX];
+ void __iomem *table[PCI_STD_NUM_BARS];
};
+enum pcim_addr_devres_type {
+ /* Default initializer. */
+ PCIM_ADDR_DEVRES_TYPE_INVALID,
+
+ /* A requested region spanning an entire BAR. */
+ PCIM_ADDR_DEVRES_TYPE_REGION,
+
+ /*
+ * A requested region spanning an entire BAR, and a mapping for
+ * the entire BAR.
+ */
+ PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING,
+
+ /*
+ * A mapping within a BAR, either spanning the whole BAR or just a
+ * range. Without a requested region.
+ */
+ PCIM_ADDR_DEVRES_TYPE_MAPPING,
+};
+
+/*
+ * This struct envelops IO or MEM addresses, i.e., mappings and region
+ * requests, because those are very frequently requested and released
+ * together.
+ */
+struct pcim_addr_devres {
+ enum pcim_addr_devres_type type;
+ void __iomem *baseaddr;
+ unsigned long offset;
+ unsigned long len;
+ int bar;
+};
+
+static inline void pcim_addr_devres_clear(struct pcim_addr_devres *res)
+{
+ memset(res, 0, sizeof(*res));
+ res->bar = -1;
+}
+
+/*
+ * The following functions, __pcim_*_region*, exist as counterparts to the
+ * versions from pci.c - which, unfortunately, can be in "hybrid mode", i.e.,
+ * sometimes managed, sometimes not.
+ *
+ * To separate the APIs cleanly, we define our own, simplified versions here.
+ */
+
+/**
+ * __pcim_request_region_range - Request a ranged region
+ * @pdev: PCI device the region belongs to
+ * @bar: BAR the range is within
+ * @offset: offset from the BAR's start address
+ * @maxlen: length in bytes, beginning at @offset
+ * @name: name associated with the request
+ * @req_flags: flags for the request, e.g., for kernel-exclusive requests
+ *
+ * Returns: 0 on success, a negative error code on failure.
+ *
+ * Request a range within a device's PCI BAR. Sanity check the input.
+ */
+static int __pcim_request_region_range(struct pci_dev *pdev, int bar,
+ unsigned long offset,
+ unsigned long maxlen,
+ const char *name, int req_flags)
+{
+ resource_size_t start = pci_resource_start(pdev, bar);
+ resource_size_t len = pci_resource_len(pdev, bar);
+ unsigned long dev_flags = pci_resource_flags(pdev, bar);
+
+ if (start == 0 || len == 0) /* Unused BAR. */
+ return 0;
+ if (len <= offset)
+ return -EINVAL;
+
+ start += offset;
+ len -= offset;
+
+ if (len > maxlen && maxlen != 0)
+ len = maxlen;
+
+ if (dev_flags & IORESOURCE_IO) {
+ if (!request_region(start, len, name))
+ return -EBUSY;
+ } else if (dev_flags & IORESOURCE_MEM) {
+ if (!__request_mem_region(start, len, name, req_flags))
+ return -EBUSY;
+ } else {
+ /* That's not a device we can request anything on. */
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static void __pcim_release_region_range(struct pci_dev *pdev, int bar,
+ unsigned long offset,
+ unsigned long maxlen)
+{
+ resource_size_t start = pci_resource_start(pdev, bar);
+ resource_size_t len = pci_resource_len(pdev, bar);
+ unsigned long flags = pci_resource_flags(pdev, bar);
+
+ if (len <= offset || start == 0)
+ return;
+
+ if (len == 0 || maxlen == 0) /* This an unused BAR. Do nothing. */
+ return;
+
+ start += offset;
+ len -= offset;
+
+ if (len > maxlen)
+ len = maxlen;
+
+ if (flags & IORESOURCE_IO)
+ release_region(start, len);
+ else if (flags & IORESOURCE_MEM)
+ release_mem_region(start, len);
+}
+
+static int __pcim_request_region(struct pci_dev *pdev, int bar,
+ const char *name, int flags)
+{
+ unsigned long offset = 0;
+ unsigned long len = pci_resource_len(pdev, bar);
+
+ return __pcim_request_region_range(pdev, bar, offset, len, name, flags);
+}
+
+static void __pcim_release_region(struct pci_dev *pdev, int bar)
+{
+ unsigned long offset = 0;
+ unsigned long len = pci_resource_len(pdev, bar);
+
+ __pcim_release_region_range(pdev, bar, offset, len);
+}
+
+static void pcim_addr_resource_release(struct device *dev, void *resource_raw)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pcim_addr_devres *res = resource_raw;
+
+ switch (res->type) {
+ case PCIM_ADDR_DEVRES_TYPE_REGION:
+ __pcim_release_region(pdev, res->bar);
+ break;
+ case PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING:
+ pci_iounmap(pdev, res->baseaddr);
+ __pcim_release_region(pdev, res->bar);
+ break;
+ case PCIM_ADDR_DEVRES_TYPE_MAPPING:
+ pci_iounmap(pdev, res->baseaddr);
+ break;
+ default:
+ break;
+ }
+}
+
+static struct pcim_addr_devres *pcim_addr_devres_alloc(struct pci_dev *pdev)
+{
+ struct pcim_addr_devres *res;
+
+ res = devres_alloc_node(pcim_addr_resource_release, sizeof(*res),
+ GFP_KERNEL, dev_to_node(&pdev->dev));
+ if (res)
+ pcim_addr_devres_clear(res);
+ return res;
+}
+
+/* Just for consistency and readability. */
+static inline void pcim_addr_devres_free(struct pcim_addr_devres *res)
+{
+ devres_free(res);
+}
+
+/*
+ * Used by devres to identify a pcim_addr_devres.
+ */
+static int pcim_addr_resources_match(struct device *dev,
+ void *a_raw, void *b_raw)
+{
+ struct pcim_addr_devres *a, *b;
+
+ a = a_raw;
+ b = b_raw;
+
+ if (a->type != b->type)
+ return 0;
+
+ switch (a->type) {
+ case PCIM_ADDR_DEVRES_TYPE_REGION:
+ case PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING:
+ return a->bar == b->bar;
+ case PCIM_ADDR_DEVRES_TYPE_MAPPING:
+ return a->baseaddr == b->baseaddr;
+ default:
+ return 0;
+ }
+}
static void devm_pci_unmap_iospace(struct device *dev, void *ptr)
{
*
* All operations are managed and will be undone on driver detach.
*
- * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
- * on failure. Usage example::
+ * Returns a pointer to the remapped memory or an IOMEM_ERR_PTR() encoded error
+ * code on failure. Usage example::
*
* res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
* base = devm_pci_remap_cfg_resource(&pdev->dev, res);
struct pci_devres *this = res;
int i;
+ /*
+ * This is legacy code.
+ *
+ * All regions requested by a pcim_ function do get released through
+ * pcim_addr_resource_release(). Thanks to the hybrid nature of the pci_
+ * region-request functions, this for-loop has to release the regions
+ * if they have been requested by such a function.
+ *
+ * TODO: Remove this once all users of pcim_enable_device() PLUS
+ * pci-region-request-functions have been ported to pcim_ functions.
+ */
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
if (mask_contains_bar(this->region_mask, i))
pci_release_region(dev, i);
static void pcim_iomap_release(struct device *gendev, void *res)
{
- struct pci_dev *dev = to_pci_dev(gendev);
- struct pcim_iomap_devres *this = res;
- int i;
-
- for (i = 0; i < PCIM_IOMAP_MAX; i++)
- if (this->table[i])
- pci_iounmap(dev, this->table[i]);
+ /*
+ * Do nothing. This is legacy code.
+ *
+ * Cleanup of the mappings is now done directly through the callbacks
+ * registered when creating them.
+ */
}
/**
* pcim_iomap_table - access iomap allocation table
* @pdev: PCI device to access iomap table for
*
+ * Returns:
+ * Const pointer to array of __iomem pointers on success, NULL on failure.
+ *
* Access iomap allocation table for @dev. If iomap table doesn't
* exist and @pdev is managed, it will be allocated. All iomaps
* recorded in the iomap table are automatically unmapped on driver
}
}
+/*
+ * The same as pcim_remove_mapping_from_legacy_table(), but identifies the
+ * mapping by its BAR index.
+ */
+static void pcim_remove_bar_from_legacy_table(struct pci_dev *pdev, int bar)
+{
+ void __iomem **legacy_iomap_table;
+
+ if (bar >= PCI_STD_NUM_BARS)
+ return;
+
+ legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
+ if (!legacy_iomap_table)
+ return;
+
+ legacy_iomap_table[bar] = NULL;
+}
+
/**
* pcim_iomap - Managed pcim_iomap()
* @pdev: PCI device to iomap for
* @bar: BAR to iomap
* @maxlen: Maximum length of iomap
*
- * Managed pci_iomap(). Map is automatically unmapped on driver
- * detach.
+ * Returns: __iomem pointer on success, NULL on failure.
+ *
+ * Managed pci_iomap(). Map is automatically unmapped on driver detach. If
+ * desired, unmap manually only with pcim_iounmap().
+ *
+ * This SHOULD only be used once per BAR.
+ *
+ * NOTE:
+ * Contrary to the other pcim_* functions, this function does not return an
+ * IOMEM_ERR_PTR() on failure, but a simple NULL. This is done for backwards
+ * compatibility.
*/
void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
{
void __iomem *mapping;
+ struct pcim_addr_devres *res;
+
+ res = pcim_addr_devres_alloc(pdev);
+ if (!res)
+ return NULL;
+ res->type = PCIM_ADDR_DEVRES_TYPE_MAPPING;
mapping = pci_iomap(pdev, bar, maxlen);
if (!mapping)
- return NULL;
+ goto err_iomap;
+ res->baseaddr = mapping;
if (pcim_add_mapping_to_legacy_table(pdev, mapping, bar) != 0)
goto err_table;
+ devres_add(&pdev->dev, res);
return mapping;
err_table:
pci_iounmap(pdev, mapping);
+err_iomap:
+ pcim_addr_devres_free(res);
return NULL;
}
EXPORT_SYMBOL(pcim_iomap);
* @pdev: PCI device to iounmap for
* @addr: Address to unmap
*
- * Managed pci_iounmap(). @addr must have been mapped using pcim_iomap().
+ * Managed pci_iounmap(). @addr must have been mapped using a pcim_* mapping
+ * function.
*/
void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr)
{
- pci_iounmap(pdev, addr);
+ struct pcim_addr_devres res_searched;
+
+ pcim_addr_devres_clear(&res_searched);
+ res_searched.type = PCIM_ADDR_DEVRES_TYPE_MAPPING;
+ res_searched.baseaddr = addr;
+
+ if (devres_release(&pdev->dev, pcim_addr_resource_release,
+ pcim_addr_resources_match, &res_searched) != 0) {
+ /* Doesn't exist. User passed nonsense. */
+ return;
+ }
pcim_remove_mapping_from_legacy_table(pdev, addr);
}
EXPORT_SYMBOL(pcim_iounmap);
+/**
+ * pcim_iomap_region - Request and iomap a PCI BAR
+ * @pdev: PCI device to map IO resources for
+ * @bar: Index of a BAR to map
+ * @name: Name associated with the request
+ *
+ * Returns: __iomem pointer on success, an IOMEM_ERR_PTR on failure.
+ *
+ * Mapping and region will get automatically released on driver detach. If
+ * desired, release manually only with pcim_iounmap_region().
+ */
+static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
+ const char *name)
+{
+ int ret;
+ struct pcim_addr_devres *res;
+
+ res = pcim_addr_devres_alloc(pdev);
+ if (!res)
+ return IOMEM_ERR_PTR(-ENOMEM);
+
+ res->type = PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING;
+ res->bar = bar;
+
+ ret = __pcim_request_region(pdev, bar, name, 0);
+ if (ret != 0)
+ goto err_region;
+
+ res->baseaddr = pci_iomap(pdev, bar, 0);
+ if (!res->baseaddr) {
+ ret = -EINVAL;
+ goto err_iomap;
+ }
+
+ devres_add(&pdev->dev, res);
+ return res->baseaddr;
+
+err_iomap:
+ __pcim_release_region(pdev, bar);
+err_region:
+ pcim_addr_devres_free(res);
+
+ return IOMEM_ERR_PTR(ret);
+}
+
+/**
+ * pcim_iounmap_region - Unmap and release a PCI BAR
+ * @pdev: PCI device to operate on
+ * @bar: Index of BAR to unmap and release
+ *
+ * Unmap a BAR and release its region manually. Only pass BARs that were
+ * previously mapped by pcim_iomap_region().
+ */
+static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
+{
+ struct pcim_addr_devres res_searched;
+
+ pcim_addr_devres_clear(&res_searched);
+ res_searched.type = PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING;
+ res_searched.bar = bar;
+
+ devres_release(&pdev->dev, pcim_addr_resource_release,
+ pcim_addr_resources_match, &res_searched);
+}
+
/**
* pcim_iomap_regions - Request and iomap PCI BARs
* @pdev: PCI device to map IO resources for
* @mask: Mask of BARs to request and iomap
- * @name: Name used when requesting regions
+ * @name: Name associated with the requests
+ *
+ * Returns: 0 on success, negative error code on failure.
*
* Request and iomap regions specified by @mask.
*/
int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
{
- void __iomem * const *iomap;
- int i, rc;
+ int ret;
+ int bar;
+ void __iomem *mapping;
- iomap = pcim_iomap_table(pdev);
- if (!iomap)
- return -ENOMEM;
+ for (bar = 0; bar < DEVICE_COUNT_RESOURCE; bar++) {
+ if (!mask_contains_bar(mask, bar))
+ continue;
- for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
- unsigned long len;
+ mapping = pcim_iomap_region(pdev, bar, name);
+ if (IS_ERR(mapping)) {
+ ret = PTR_ERR(mapping);
+ goto err;
+ }
+ ret = pcim_add_mapping_to_legacy_table(pdev, mapping, bar);
+ if (ret != 0)
+ goto err;
+ }
- if (!mask_contains_bar(mask, i))
- continue;
+ return 0;
+
+err:
+ while (--bar >= 0) {
+ pcim_iounmap_region(pdev, bar);
+ pcim_remove_bar_from_legacy_table(pdev, bar);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(pcim_iomap_regions);
- rc = -EINVAL;
- len = pci_resource_len(pdev, i);
- if (!len)
- goto err_inval;
+static int _pcim_request_region(struct pci_dev *pdev, int bar, const char *name,
+ int request_flags)
+{
+ int ret;
+ struct pcim_addr_devres *res;
- rc = pci_request_region(pdev, i, name);
- if (rc)
- goto err_inval;
+ res = pcim_addr_devres_alloc(pdev);
+ if (!res)
+ return -ENOMEM;
+ res->type = PCIM_ADDR_DEVRES_TYPE_REGION;
+ res->bar = bar;
- rc = -ENOMEM;
- if (!pcim_iomap(pdev, i, 0))
- goto err_region;
+ ret = __pcim_request_region(pdev, bar, name, request_flags);
+ if (ret != 0) {
+ pcim_addr_devres_free(res);
+ return ret;
}
+ devres_add(&pdev->dev, res);
return 0;
+}
- err_region:
- pci_release_region(pdev, i);
- err_inval:
- while (--i >= 0) {
- if (!mask_contains_bar(mask, i))
- continue;
- pcim_iounmap(pdev, iomap[i]);
- pci_release_region(pdev, i);
+/**
+ * pcim_request_region - Request a PCI BAR
+ * @pdev: PCI device to requestion region for
+ * @bar: Index of BAR to request
+ * @name: Name associated with the request
+ *
+ * Returns: 0 on success, a negative error code on failure.
+ *
+ * Request region specified by @bar.
+ *
+ * The region will automatically be released on driver detach. If desired,
+ * release manually only with pcim_release_region().
+ */
+static int pcim_request_region(struct pci_dev *pdev, int bar, const char *name)
+{
+ return _pcim_request_region(pdev, bar, name, 0);
+}
+
+/**
+ * pcim_release_region - Release a PCI BAR
+ * @pdev: PCI device to operate on
+ * @bar: Index of BAR to release
+ *
+ * Release a region manually that was previously requested by
+ * pcim_request_region().
+ */
+static void pcim_release_region(struct pci_dev *pdev, int bar)
+{
+ struct pcim_addr_devres res_searched;
+
+ pcim_addr_devres_clear(&res_searched);
+ res_searched.type = PCIM_ADDR_DEVRES_TYPE_REGION;
+ res_searched.bar = bar;
+
+ devres_release(&pdev->dev, pcim_addr_resource_release,
+ pcim_addr_resources_match, &res_searched);
+}
+
+
+/**
+ * pcim_release_all_regions - Release all regions of a PCI-device
+ * @pdev: the PCI device
+ *
+ * Release all regions previously requested through pcim_request_region()
+ * or pcim_request_all_regions().
+ *
+ * Can be called from any context, i.e., not necessarily as a counterpart to
+ * pcim_request_all_regions().
+ */
+static void pcim_release_all_regions(struct pci_dev *pdev)
+{
+ int bar;
+
+ for (bar = 0; bar < PCI_STD_NUM_BARS; bar++)
+ pcim_release_region(pdev, bar);
+}
+
+/**
+ * pcim_request_all_regions - Request all regions
+ * @pdev: PCI device to map IO resources for
+ * @name: name associated with the request
+ *
+ * Returns: 0 on success, negative error code on failure.
+ *
+ * Requested regions will automatically be released at driver detach. If
+ * desired, release individual regions with pcim_release_region() or all of
+ * them at once with pcim_release_all_regions().
+ */
+static int pcim_request_all_regions(struct pci_dev *pdev, const char *name)
+{
+ int ret;
+ int bar;
+
+ for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
+ ret = pcim_request_region(pdev, bar, name);
+ if (ret != 0)
+ goto err;
}
- return rc;
+ return 0;
+
+err:
+ pcim_release_all_regions(pdev);
+
+ return ret;
}
-EXPORT_SYMBOL(pcim_iomap_regions);
/**
* pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
* @pdev: PCI device to map IO resources for
* @mask: Mask of BARs to iomap
- * @name: Name used when requesting regions
+ * @name: Name associated with the requests
+ *
+ * Returns: 0 on success, negative error code on failure.
*
* Request all PCI BARs and iomap regions specified by @mask.
+ *
+ * To release these resources manually, call pcim_release_region() for the
+ * regions and pcim_iounmap() for the mappings.
*/
int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
const char *name)
{
- int request_mask = ((1 << 6) - 1) & ~mask;
- int rc;
+ int bar;
+ int ret;
+ void __iomem **legacy_iomap_table;
- rc = pci_request_selected_regions(pdev, request_mask, name);
- if (rc)
- return rc;
+ ret = pcim_request_all_regions(pdev, name);
+ if (ret != 0)
+ return ret;
- rc = pcim_iomap_regions(pdev, mask, name);
- if (rc)
- pci_release_selected_regions(pdev, request_mask);
- return rc;
+ for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
+ if (!mask_contains_bar(mask, bar))
+ continue;
+ if (!pcim_iomap(pdev, bar, 0))
+ goto err;
+ }
+
+ return 0;
+
+err:
+ /*
+ * If bar is larger than 0, then pcim_iomap() above has most likely
+ * failed because of -EINVAL. If it is equal 0, most likely the table
+ * couldn't be created, indicating -ENOMEM.
+ */
+ ret = bar > 0 ? -EINVAL : -ENOMEM;
+ legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
+
+ while (--bar >= 0)
+ pcim_iounmap(pdev, legacy_iomap_table[bar]);
+
+ pcim_release_all_regions(pdev);
+
+ return ret;
}
EXPORT_SYMBOL(pcim_iomap_regions_request_all);
*/
void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
{
- void __iomem * const *iomap;
int i;
- iomap = pcim_iomap_table(pdev);
- if (!iomap)
- return;
-
- for (i = 0; i < PCIM_IOMAP_MAX; i++) {
+ for (i = 0; i < PCI_STD_NUM_BARS; i++) {
if (!mask_contains_bar(mask, i))
continue;
- pcim_iounmap(pdev, iomap[i]);
- pci_release_region(pdev, i);
+ pcim_iounmap_region(pdev, i);
+ pcim_remove_bar_from_legacy_table(pdev, i);
}
}
EXPORT_SYMBOL(pcim_iounmap_regions);
projects / users / jedix / linux-maple.git / commitdiff