Re: [PATCH] dma: ti: k3-udma: Fix rflow reservation for PKTDMA

[Tom Rini]

On Thu, Dec 23, 2021 at 07:27:30PM +0530, Vignesh Raghavendra wrote:

> Driver has a bug in that it uses rflow_in_use bitmap when setting up free 
> rflow range
> from TISCI but use rflow_map for reservation in __udma_reserve_rflow()
> 
> Fix this by dropping rflow_in_use bitmap array and use rflow_map for
> PKTDMA. BCDMA does not need rflow_in_use either.
> 
> This fixes CPSW3g not able to get DMA channels at R5 SPL on AM64x
> 
> Signed-off-by: Vignesh Raghavendra 

Applied to u-boot/master, thanks!

-- 
Tom


signature.asc
Description: PGP signature

[PATCH] dma: ti: k3-udma: Fix rflow reservation for PKTDMA

[Vignesh Raghavendra]

Driver has a bug in that it uses rflow_in_use bitmap when setting up free rflow 
range
from TISCI but use rflow_map for reservation in __udma_reserve_rflow()

Fix this by dropping rflow_in_use bitmap array and use rflow_map for
PKTDMA. BCDMA does not need rflow_in_use either.

This fixes CPSW3g not able to get DMA channels at R5 SPL on AM64x

Signed-off-by: Vignesh Raghavendra 
---
 drivers/dma/ti/k3-udma.c | 21 -
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 411edef3a7..86603d43f1 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -165,7 +165,6 @@ struct udma_dev {
unsigned long *rchan_map;
unsigned long *rflow_map;
unsigned long *rflow_map_reserved;
-   unsigned long *rflow_in_use;
unsigned long *tflow_map;
 
struct udma_bchan *bchans;
@@ -1448,15 +1447,11 @@ static int bcdma_setup_resources(struct udma_dev *ud)
   sizeof(unsigned long), GFP_KERNEL);
ud->rchans = devm_kcalloc(dev, ud->rchan_cnt, sizeof(*ud->rchans),
  GFP_KERNEL);
-   /* BCDMA do not really have flows, but the driver expect it */
-   ud->rflow_in_use = devm_kcalloc(dev, BITS_TO_LONGS(ud->rchan_cnt),
-   sizeof(unsigned long),
-   GFP_KERNEL);
ud->rflows = devm_kcalloc(dev, ud->rchan_cnt, sizeof(*ud->rflows),
  GFP_KERNEL);
 
if (!ud->bchan_map || !ud->tchan_map || !ud->rchan_map ||
-   !ud->rflow_in_use || !ud->bchans || !ud->tchans || !ud->rchans ||
+   !ud->bchans || !ud->tchans || !ud->rchans ||
!ud->rflows)
return -ENOMEM;
 
@@ -1535,16 +1530,16 @@ static int pktdma_setup_resources(struct udma_dev *ud)
   sizeof(unsigned long), GFP_KERNEL);
ud->rchans = devm_kcalloc(dev, ud->rchan_cnt, sizeof(*ud->rchans),
  GFP_KERNEL);
-   ud->rflow_in_use = devm_kcalloc(dev, BITS_TO_LONGS(ud->rflow_cnt),
-   sizeof(unsigned long),
-   GFP_KERNEL);
+   ud->rflow_map = devm_kcalloc(dev, BITS_TO_LONGS(ud->rflow_cnt),
+sizeof(unsigned long),
+GFP_KERNEL);
ud->rflows = devm_kcalloc(dev, ud->rflow_cnt, sizeof(*ud->rflows),
  GFP_KERNEL);
ud->tflow_map = devm_kmalloc_array(dev, BITS_TO_LONGS(ud->tflow_cnt),
   sizeof(unsigned long), GFP_KERNEL);
 
if (!ud->tchan_map || !ud->rchan_map || !ud->tflow_map || !ud->tchans ||
-   !ud->rchans || !ud->rflows || !ud->rflow_in_use)
+   !ud->rchans || !ud->rflows || !ud->rflow_map)
return -ENOMEM;
 
/* Get resource ranges from tisci */
@@ -1592,12 +1587,12 @@ static int pktdma_setup_resources(struct udma_dev *ud)
rm_res = tisci_rm->rm_ranges[RM_RANGE_RFLOW];
if (IS_ERR(rm_res)) {
/* all rflows are assigned exclusively to Linux */
-   bitmap_zero(ud->rflow_in_use, ud->rflow_cnt);
+   bitmap_zero(ud->rflow_map, ud->rflow_cnt);
} else {
-   bitmap_fill(ud->rflow_in_use, ud->rflow_cnt);
+   bitmap_fill(ud->rflow_map, ud->rflow_cnt);
for (i = 0; i < rm_res->sets; i++) {
rm_desc = &rm_res->desc[i];
-   bitmap_clear(ud->rflow_in_use, rm_desc->start,
+   bitmap_clear(ud->rflow_map, rm_desc->start,
 rm_desc->num);
dev_dbg(dev, "ti-sci-res: rflow: %d:%d\n",
rm_desc->start, rm_desc->num);
-- 
2.34.1