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path: root/drivers/staging/kpc2000/kpc_dma/dma.c
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Diffstat (limited to 'drivers/staging/kpc2000/kpc_dma/dma.c')
-rw-r--r--drivers/staging/kpc2000/kpc_dma/dma.c142
1 files changed, 70 insertions, 72 deletions
diff --git a/drivers/staging/kpc2000/kpc_dma/dma.c b/drivers/staging/kpc2000/kpc_dma/dma.c
index 6959bac11388..51a4dd534a0d 100644
--- a/drivers/staging/kpc2000/kpc_dma/dma.c
+++ b/drivers/staging/kpc2000/kpc_dma/dma.c
@@ -2,7 +2,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
-#include <asm/io.h>
+#include <linux/io.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
@@ -14,11 +14,11 @@
static
irqreturn_t ndd_irq_handler(int irq, void *dev_id)
{
- struct kpc_dma_device *ldev = (struct kpc_dma_device*)dev_id;
-
+ struct kpc_dma_device *ldev = (struct kpc_dma_device *)dev_id;
+
if ((GetEngineControl(ldev) & ENG_CTL_IRQ_ACTIVE) || (ldev->desc_completed->MyDMAAddr != GetEngineCompletePtr(ldev)))
schedule_work(&ldev->irq_work);
-
+
return IRQ_HANDLED;
}
@@ -27,217 +27,215 @@ void ndd_irq_worker(struct work_struct *ws)
{
struct kpc_dma_descriptor *cur;
struct kpc_dma_device *eng = container_of(ws, struct kpc_dma_device, irq_work);
+
lock_engine(eng);
-
+
if (GetEngineCompletePtr(eng) == 0)
goto out;
-
+
if (eng->desc_completed->MyDMAAddr == GetEngineCompletePtr(eng))
goto out;
-
+
cur = eng->desc_completed;
do {
cur = cur->Next;
dev_dbg(&eng->pldev->dev, "Handling completed descriptor %p (acd = %p)\n", cur, cur->acd);
BUG_ON(cur == eng->desc_next); // Ordering failure.
-
- if (cur->DescControlFlags & DMA_DESC_CTL_SOP){
+
+ if (cur->DescControlFlags & DMA_DESC_CTL_SOP) {
eng->accumulated_bytes = 0;
eng->accumulated_flags = 0;
}
-
+
eng->accumulated_bytes += cur->DescByteCount;
if (cur->DescStatusFlags & DMA_DESC_STS_ERROR)
eng->accumulated_flags |= ACD_FLAG_ENG_ACCUM_ERROR;
-
+
if (cur->DescStatusFlags & DMA_DESC_STS_SHORT)
eng->accumulated_flags |= ACD_FLAG_ENG_ACCUM_SHORT;
-
- if (cur->DescControlFlags & DMA_DESC_CTL_EOP){
+
+ if (cur->DescControlFlags & DMA_DESC_CTL_EOP) {
if (cur->acd)
transfer_complete_cb(cur->acd, eng->accumulated_bytes, eng->accumulated_flags | ACD_FLAG_DONE);
}
-
+
eng->desc_completed = cur;
} while (cur->MyDMAAddr != GetEngineCompletePtr(eng));
-
+
out:
SetClearEngineControl(eng, ENG_CTL_IRQ_ACTIVE, 0);
-
+
unlock_engine(eng);
}
-
/********** DMA Engine Init/Teardown **********/
void start_dma_engine(struct kpc_dma_device *eng)
{
eng->desc_next = eng->desc_pool_first;
eng->desc_completed = eng->desc_pool_last;
-
+
// Setup the engine pointer registers
SetEngineNextPtr(eng, eng->desc_pool_first);
SetEngineSWPtr(eng, eng->desc_pool_first);
ClearEngineCompletePtr(eng);
-
+
WriteEngineControl(eng, ENG_CTL_DMA_ENABLE | ENG_CTL_IRQ_ENABLE);
}
int setup_dma_engine(struct kpc_dma_device *eng, u32 desc_cnt)
{
u32 caps;
- struct kpc_dma_descriptor * cur;
- struct kpc_dma_descriptor * next;
+ struct kpc_dma_descriptor *cur;
+ struct kpc_dma_descriptor *next;
dma_addr_t next_handle;
dma_addr_t head_handle;
unsigned int i;
int rv;
- dev_dbg(&eng->pldev->dev, "Setting up DMA engine [%p]\n", eng);
-
+
caps = GetEngineCapabilities(eng);
-
- if (WARN(!(caps & ENG_CAP_PRESENT), "setup_dma_engine() called for DMA Engine at %p which isn't present in hardware!\n", eng))
+
+ if (WARN(!(caps & ENG_CAP_PRESENT), "%s() called for DMA Engine at %p which isn't present in hardware!\n", __func__, eng))
return -ENXIO;
-
- if (caps & ENG_CAP_DIRECTION){
+
+ if (caps & ENG_CAP_DIRECTION) {
eng->dir = DMA_FROM_DEVICE;
} else {
eng->dir = DMA_TO_DEVICE;
}
-
+
eng->desc_pool_cnt = desc_cnt;
eng->desc_pool = dma_pool_create("KPC DMA Descriptors", &eng->pldev->dev, sizeof(struct kpc_dma_descriptor), DMA_DESC_ALIGNMENT, 4096);
-
+
eng->desc_pool_first = dma_pool_alloc(eng->desc_pool, GFP_KERNEL | GFP_DMA, &head_handle);
- if (!eng->desc_pool_first){
- dev_err(&eng->pldev->dev, "setup_dma_engine: couldn't allocate desc_pool_first!\n");
+ if (!eng->desc_pool_first) {
+ dev_err(&eng->pldev->dev, "%s: couldn't allocate desc_pool_first!\n", __func__);
dma_pool_destroy(eng->desc_pool);
return -ENOMEM;
}
-
+
eng->desc_pool_first->MyDMAAddr = head_handle;
clear_desc(eng->desc_pool_first);
-
+
cur = eng->desc_pool_first;
- for (i = 1 ; i < eng->desc_pool_cnt ; i++){
+ for (i = 1 ; i < eng->desc_pool_cnt ; i++) {
next = dma_pool_alloc(eng->desc_pool, GFP_KERNEL | GFP_DMA, &next_handle);
- if (next == NULL)
+ if (!next)
goto done_alloc;
-
+
clear_desc(next);
next->MyDMAAddr = next_handle;
-
+
cur->DescNextDescPtr = next_handle;
cur->Next = next;
cur = next;
}
-
+
done_alloc:
// Link the last descriptor back to the first, so it's a circular linked list
cur->Next = eng->desc_pool_first;
cur->DescNextDescPtr = eng->desc_pool_first->MyDMAAddr;
-
+
eng->desc_pool_last = cur;
eng->desc_completed = eng->desc_pool_last;
-
+
// Setup work queue
INIT_WORK(&eng->irq_work, ndd_irq_worker);
-
+
// Grab IRQ line
rv = request_irq(eng->irq, ndd_irq_handler, IRQF_SHARED, KP_DRIVER_NAME_DMA_CONTROLLER, eng);
- if (rv){
- dev_err(&eng->pldev->dev, "setup_dma_engine: failed to request_irq: %d\n", rv);
+ if (rv) {
+ dev_err(&eng->pldev->dev, "%s: failed to request_irq: %d\n", __func__, rv);
return rv;
}
-
+
// Turn on the engine!
start_dma_engine(eng);
unlock_engine(eng);
-
+
return 0;
}
void stop_dma_engine(struct kpc_dma_device *eng)
{
unsigned long timeout;
- dev_dbg(&eng->pldev->dev, "Destroying DMA engine [%p]\n", eng);
-
+
// Disable the descriptor engine
WriteEngineControl(eng, 0);
-
+
// Wait for descriptor engine to finish current operaion
timeout = jiffies + (HZ / 2);
- while (GetEngineControl(eng) & ENG_CTL_DMA_RUNNING){
- if (time_after(jiffies, timeout)){
+ while (GetEngineControl(eng) & ENG_CTL_DMA_RUNNING) {
+ if (time_after(jiffies, timeout)) {
dev_crit(&eng->pldev->dev, "DMA_RUNNING still asserted!\n");
break;
}
}
-
+
// Request a reset
WriteEngineControl(eng, ENG_CTL_DMA_RESET_REQUEST);
-
+
// Wait for reset request to be processed
timeout = jiffies + (HZ / 2);
- while (GetEngineControl(eng) & (ENG_CTL_DMA_RUNNING | ENG_CTL_DMA_RESET_REQUEST)){
- if (time_after(jiffies, timeout)){
+ while (GetEngineControl(eng) & (ENG_CTL_DMA_RUNNING | ENG_CTL_DMA_RESET_REQUEST)) {
+ if (time_after(jiffies, timeout)) {
dev_crit(&eng->pldev->dev, "ENG_CTL_DMA_RESET_REQUEST still asserted!\n");
break;
}
}
-
+
// Request a reset
WriteEngineControl(eng, ENG_CTL_DMA_RESET);
-
+
// And wait for reset to complete
timeout = jiffies + (HZ / 2);
- while (GetEngineControl(eng) & ENG_CTL_DMA_RESET){
- if (time_after(jiffies, timeout)){
+ while (GetEngineControl(eng) & ENG_CTL_DMA_RESET) {
+ if (time_after(jiffies, timeout)) {
dev_crit(&eng->pldev->dev, "DMA_RESET still asserted!\n");
break;
}
}
-
+
// Clear any persistent bits just to make sure there is no residue from the reset
SetClearEngineControl(eng, (ENG_CTL_IRQ_ACTIVE | ENG_CTL_DESC_COMPLETE | ENG_CTL_DESC_ALIGN_ERR | ENG_CTL_DESC_FETCH_ERR | ENG_CTL_SW_ABORT_ERR | ENG_CTL_DESC_CHAIN_END | ENG_CTL_DMA_WAITING_PERSIST), 0);
-
+
// Reset performance counters
-
+
// Completely disable the engine
WriteEngineControl(eng, 0);
}
void destroy_dma_engine(struct kpc_dma_device *eng)
{
- struct kpc_dma_descriptor * cur;
+ struct kpc_dma_descriptor *cur;
dma_addr_t cur_handle;
unsigned int i;
-
+
stop_dma_engine(eng);
-
+
cur = eng->desc_pool_first;
cur_handle = eng->desc_pool_first->MyDMAAddr;
-
- for (i = 0 ; i < eng->desc_pool_cnt ; i++){
+
+ for (i = 0 ; i < eng->desc_pool_cnt ; i++) {
struct kpc_dma_descriptor *next = cur->Next;
dma_addr_t next_handle = cur->DescNextDescPtr;
+
dma_pool_free(eng->desc_pool, cur, cur_handle);
cur_handle = next_handle;
cur = next;
}
-
+
dma_pool_destroy(eng->desc_pool);
-
+
free_irq(eng->irq, eng);
}
-
-
/********** Helper Functions **********/
int count_descriptors_available(struct kpc_dma_device *eng)
{
u32 count = 0;
struct kpc_dma_descriptor *cur = eng->desc_next;
- while (cur != eng->desc_completed){
+
+ while (cur != eng->desc_completed) {
BUG_ON(cur == NULL);
count++;
cur = cur->Next;
@@ -247,7 +245,7 @@ int count_descriptors_available(struct kpc_dma_device *eng)
void clear_desc(struct kpc_dma_descriptor *desc)
{
- if (desc == NULL)
+ if (!desc)
return;
desc->DescByteCount = 0;
desc->DescStatusErrorFlags = 0;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.