[RESEND 3/4] vme: change bus error handling scheme
dmitry.kalinkin at gmail.com
dmitry.kalinkin at gmail.com
Thu Sep 17 23:01:44 UTC 2015
From: Dmitry Kalinkin <dmitry.kalinkin at gmail.com>
The current VME bus error handler adds errors to the bridge error list.
vme_master_{read,write} then traverses that list to look for relevant
errors.
Such scheme didn't work well for accesses going through vme_master_mmap
because they would also allocate a vme_bus_error, but have no way to do
vme_clear_errors call to free that memory.
This changes the error handling process to be other way around: now
vme_master_{read,write} defines a window in VME address space that will
catch possible errors. VME bus error interrupt only traverses these
windows and marks those that had errors in them.
Signed-off-by: Dmitry Kalinkin <dmitry.kalinkin at gmail.com>
Cc: Igor Alekseev <igor.alekseev at itep.ru>
---
drivers/vme/bridges/vme_ca91cx42.c | 3 +-
drivers/vme/bridges/vme_tsi148.c | 83 ++++++++++++++++----------------
drivers/vme/vme.c | 92 +++++++++++++-----------------------
drivers/vme/vme_bridge.h | 23 +++++----
4 files changed, 91 insertions(+), 110 deletions(-)
diff --git a/drivers/vme/bridges/vme_ca91cx42.c b/drivers/vme/bridges/vme_ca91cx42.c
index f692efc..834883d 100644
--- a/drivers/vme/bridges/vme_ca91cx42.c
+++ b/drivers/vme/bridges/vme_ca91cx42.c
@@ -204,8 +204,7 @@ static int ca91cx42_irq_init(struct vme_bridge *ca91cx42_bridge)
/* Need pdev */
pdev = container_of(ca91cx42_bridge->parent, struct pci_dev, dev);
- /* Initialise list for VME bus errors */
- INIT_LIST_HEAD(&ca91cx42_bridge->vme_errors);
+ INIT_LIST_HEAD(&ca91cx42_bridge->vme_error_handlers);
mutex_init(&ca91cx42_bridge->irq_mtx);
diff --git a/drivers/vme/bridges/vme_tsi148.c b/drivers/vme/bridges/vme_tsi148.c
index 76ccfae..b0132e0 100644
--- a/drivers/vme/bridges/vme_tsi148.c
+++ b/drivers/vme/bridges/vme_tsi148.c
@@ -314,8 +314,7 @@ static int tsi148_irq_init(struct vme_bridge *tsi148_bridge)
bridge = tsi148_bridge->driver_priv;
- /* Initialise list for VME bus errors */
- INIT_LIST_HEAD(&tsi148_bridge->vme_errors);
+ INIT_LIST_HEAD(&tsi148_bridge->vme_error_handlers);
mutex_init(&tsi148_bridge->irq_mtx);
@@ -1187,7 +1186,7 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
int retval, enabled;
unsigned long long vme_base, size;
u32 aspace, cycle, dwidth;
- struct vme_bus_error *vme_err = NULL;
+ struct vme_error_handler *handler;
struct vme_bridge *tsi148_bridge;
void __iomem *addr = image->kern_base + offset;
unsigned int done = 0;
@@ -1197,6 +1196,17 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
spin_lock(&image->lock);
+ if (err_chk) {
+ __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace,
+ &cycle, &dwidth);
+ handler = vme_register_error_handler(tsi148_bridge, aspace,
+ vme_base + offset, count);
+ if (!handler) {
+ spin_unlock(&image->lock);
+ return -ENOMEM;
+ }
+ }
+
/* The following code handles VME address alignment. We cannot use
* memcpy_xxx here because it may cut data transfers in to 8-bit
* cycles when D16 or D32 cycles are required on the VME bus.
@@ -1240,24 +1250,16 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
out:
retval = count;
- if (!err_chk)
- goto skip_chk;
-
- __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, &cycle,
- &dwidth);
-
- vme_err = vme_find_error(tsi148_bridge, aspace, vme_base + offset,
- count);
- if (vme_err != NULL) {
- dev_err(image->parent->parent, "First VME read error detected "
- "an at address 0x%llx\n", vme_err->address);
- retval = vme_err->address - (vme_base + offset);
- /* Clear down save errors in this address range */
- vme_clear_errors(tsi148_bridge, aspace, vme_base + offset,
- count);
+ if (err_chk) {
+ if (handler->num_errors) {
+ dev_err(image->parent->parent,
+ "First VME read error detected an at address 0x%llx\n",
+ handler->first_error);
+ retval = handler->first_error - (vme_base + offset);
+ }
+ vme_unregister_error_handler(handler);
}
-skip_chk:
spin_unlock(&image->lock);
return retval;
@@ -1274,7 +1276,7 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
unsigned int done = 0;
unsigned int count32;
- struct vme_bus_error *vme_err = NULL;
+ struct vme_error_handler *handler;
struct vme_bridge *tsi148_bridge;
struct tsi148_driver *bridge;
@@ -1284,6 +1286,17 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
spin_lock(&image->lock);
+ if (err_chk) {
+ __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace,
+ &cycle, &dwidth);
+ handler = vme_register_error_handler(tsi148_bridge, aspace,
+ vme_base + offset, count);
+ if (!handler) {
+ spin_unlock(&image->lock);
+ return -ENOMEM;
+ }
+ }
+
/* Here we apply for the same strategy we do in master_read
* function in order to assure the correct cycles.
*/
@@ -1333,30 +1346,18 @@ out:
* We check for saved errors in the written address range/space.
*/
- if (!err_chk)
- goto skip_chk;
-
- /*
- * Get window info first, to maximise the time that the buffers may
- * fluch on their own
- */
- __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, &cycle,
- &dwidth);
-
- ioread16(bridge->flush_image->kern_base + 0x7F000);
+ if (err_chk) {
+ ioread16(bridge->flush_image->kern_base + 0x7F000);
- vme_err = vme_find_error(tsi148_bridge, aspace, vme_base + offset,
- count);
- if (vme_err != NULL) {
- dev_warn(tsi148_bridge->parent, "First VME write error detected"
- " an at address 0x%llx\n", vme_err->address);
- retval = vme_err->address - (vme_base + offset);
- /* Clear down save errors in this address range */
- vme_clear_errors(tsi148_bridge, aspace, vme_base + offset,
- count);
+ if (handler->num_errors) {
+ dev_warn(tsi148_bridge->parent,
+ "First VME write error detected an at address 0x%llx\n",
+ handler->first_error);
+ retval = handler->first_error - (vme_base + offset);
+ }
+ vme_unregister_error_handler(handler);
}
-skip_chk:
spin_unlock(&image->lock);
return retval;
diff --git a/drivers/vme/vme.c b/drivers/vme/vme.c
index 2b79cd2..7a10d92 100644
--- a/drivers/vme/vme.c
+++ b/drivers/vme/vme.c
@@ -1026,76 +1026,52 @@ EXPORT_SYMBOL(vme_dma_free);
void vme_bus_error_handler(struct vme_bridge *bridge,
unsigned long long address, int am)
{
- struct vme_bus_error *error;
-
- error = kmalloc(sizeof(struct vme_bus_error), GFP_ATOMIC);
- if (error) {
- error->aspace = vme_get_aspace(am);
- error->address = address;
- list_add_tail(&error->list, &bridge->vme_errors);
- } else {
- dev_err(bridge->parent,
- "Unable to alloc memory for VMEbus Error reporting\n");
+ struct list_head *handler_pos = NULL;
+ struct vme_error_handler *handler;
+ u32 aspace = vme_get_aspace(am);
+
+ list_for_each(handler_pos, &bridge->vme_error_handlers) {
+ handler = list_entry(handler_pos, struct vme_error_handler,
+ list);
+ if ((aspace == handler->aspace) &&
+ (address >= handler->start) &&
+ (address < handler->end)) {
+ if (!handler->num_errors)
+ handler->first_error = address;
+ if (handler->num_errors != UINT_MAX)
+ handler->num_errors++;
+ }
}
}
EXPORT_SYMBOL(vme_bus_error_handler);
-/*
- * Find the first error in this address range
- */
-struct vme_bus_error *vme_find_error(struct vme_bridge *bridge, u32 aspace,
- unsigned long long address, size_t count)
+struct vme_error_handler *vme_register_error_handler(
+ struct vme_bridge *bridge, u32 aspace,
+ unsigned long long address, size_t len)
{
- struct list_head *err_pos;
- struct vme_bus_error *vme_err, *valid = NULL;
- unsigned long long bound;
-
- bound = address + count;
+ struct vme_error_handler *handler;
- err_pos = NULL;
- /* Iterate through errors */
- list_for_each(err_pos, &bridge->vme_errors) {
- vme_err = list_entry(err_pos, struct vme_bus_error, list);
- if ((vme_err->aspace == aspace) &&
- (vme_err->address >= address) &&
- (vme_err->address < bound)) {
+ handler = kmalloc(sizeof(*handler), GFP_KERNEL);
+ if (!handler)
+ return NULL;
- valid = vme_err;
- break;
- }
- }
+ handler->aspace = aspace;
+ handler->start = address;
+ handler->end = address + len;
+ handler->num_errors = 0;
+ handler->first_error = 0;
+ list_add_tail(&handler->list, &bridge->vme_error_handlers);
- return valid;
+ return handler;
}
-EXPORT_SYMBOL(vme_find_error);
+EXPORT_SYMBOL(vme_register_error_handler);
-/*
- * Clear errors in the provided address range.
- */
-void vme_clear_errors(struct vme_bridge *bridge, u32 aspace,
- unsigned long long address, size_t count)
+void vme_unregister_error_handler(struct vme_error_handler *handler)
{
- struct list_head *err_pos, *temp;
- struct vme_bus_error *vme_err;
- unsigned long long bound;
-
- bound = address + count;
-
- err_pos = NULL;
- /* Iterate through errors */
- list_for_each_safe(err_pos, temp, &bridge->vme_errors) {
- vme_err = list_entry(err_pos, struct vme_bus_error, list);
-
- if ((vme_err->aspace == aspace) &&
- (vme_err->address >= address) &&
- (vme_err->address < bound)) {
-
- list_del(err_pos);
- kfree(vme_err);
- }
- }
+ list_del(&handler->list);
+ kfree(handler);
}
-EXPORT_SYMBOL(vme_clear_errors);
+EXPORT_SYMBOL(vme_unregister_error_handler);
void vme_irq_handler(struct vme_bridge *bridge, int level, int statid)
{
diff --git a/drivers/vme/vme_bridge.h b/drivers/vme/vme_bridge.h
index 92fbe18..397578a 100644
--- a/drivers/vme/vme_bridge.h
+++ b/drivers/vme/vme_bridge.h
@@ -75,10 +75,13 @@ struct vme_lm_resource {
int monitors;
};
-struct vme_bus_error {
+struct vme_error_handler {
struct list_head list;
- u32 aspace;
- unsigned long long address;
+ unsigned long long start; /* Beginning of error window */
+ unsigned long long end; /* End of error window */
+ unsigned long long first_error; /* Address of the first error */
+ u32 aspace; /* Address space of error window*/
+ unsigned num_errors; /* Number of errors */
};
struct vme_callback {
@@ -106,8 +109,10 @@ struct vme_bridge {
struct list_head dma_resources;
struct list_head lm_resources;
- struct list_head vme_errors; /* List for errors generated on VME */
- struct list_head devices; /* List of devices on this bridge */
+ /* List for registered errors handlers */
+ struct list_head vme_error_handlers;
+ /* List of devices on this bridge */
+ struct list_head devices;
/* Bridge Info - XXX Move to private structure? */
struct device *parent; /* Parent device (eg. pdev->dev for PCI) */
@@ -168,13 +173,13 @@ struct vme_bridge {
void vme_bus_error_handler(struct vme_bridge *bridge,
unsigned long long address, int am);
-struct vme_bus_error *vme_find_error(struct vme_bridge *bridge, u32 aspace,
- unsigned long long address, size_t count);
-void vme_clear_errors(struct vme_bridge *bridge, u32 aspace,
- unsigned long long address, size_t count);
void vme_irq_handler(struct vme_bridge *, int, int);
int vme_register_bridge(struct vme_bridge *);
void vme_unregister_bridge(struct vme_bridge *);
+struct vme_error_handler *vme_register_error_handler(
+ struct vme_bridge *bridge, u32 aspace,
+ unsigned long long address, size_t len);
+void vme_unregister_error_handler(struct vme_error_handler *handler);
#endif /* _VME_BRIDGE_H_ */
--
1.7.10.4
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