[net-next PATCH] driver: net: cpsw: add no_bd_ram dt parsing

[net-next PATCH] driver: net: cpsw: add no_bd_ram dt parsing

[Mugunthan V N]

cpdma is capable of placing the dma descriptors in ddr using
dma_alloc_coherent() when the internal bd ram size is not enough.
To utilize this feature pass the DT parameter "no_bd_ram" and
increase bd_ram_size and number of rx descriptors.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c | 4 ++++
 drivers/net/ethernet/ti/cpsw.h | 1 +
 2 files changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 8fc90f1..cf1a625 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1987,6 +1987,8 @@ static int cpsw_probe_dt(struct cpsw_platform_data *data,
 	}
 	data->ale_entries = prop;
 
+	data->no_bd_ram = of_property_read_bool(node, "no_bd_ram");
+
 	if (of_property_read_u32(node, "bd_ram_size", &prop)) {
 		dev_err(&pdev->dev, "Missing bd_ram_size property in the DT.\n");
 		return -EINVAL;
@@ -2358,6 +2360,8 @@ static int cpsw_probe(struct platform_device *pdev)
 	dma_params.desc_mem_size	= data->bd_ram_size;
 	dma_params.desc_align		= 16;
 	dma_params.has_ext_regs		= true;
+	if (data->no_bd_ram)
+		dma_params.desc_mem_phys = 0;
 	dma_params.desc_hw_addr         = dma_params.desc_mem_phys;
 
 	priv->dma = cpdma_ctlr_create(&dma_params);
diff --git a/drivers/net/ethernet/ti/cpsw.h b/drivers/net/ethernet/ti/cpsw.h
index ca90efa..b654ac2 100644
--- a/drivers/net/ethernet/ti/cpsw.h
+++ b/drivers/net/ethernet/ti/cpsw.h
@@ -33,6 +33,7 @@ struct cpsw_platform_data {
 	u32	cpts_clock_mult;  /* convert input clock ticks to nanoseconds */
 	u32	cpts_clock_shift; /* convert input clock ticks to nanoseconds */
 	u32	ale_entries;	/* ale table size */
+	bool	no_bd_ram;	/* set if cpsw bd ram should not be used */
 	u32	bd_ram_size;  /*buffer descriptor ram size */
 	u32	rx_descs;	/* Number of Rx Descriptios */
 	u32	mac_control;	/* Mac control register */
-- 
2.6.1.133.gf5b6079

Re: [net-next PATCH] driver: net: cpsw: add no_bd_ram dt parsing

[Mugunthan V N]

On Friday 09 October 2015 03:36 PM, Mugunthan V N wrote:
> cpdma is capable of placing the dma descriptors in ddr using
> dma_alloc_coherent() when the internal bd ram size is not enough.
> To utilize this feature pass the DT parameter "no_bd_ram" and
> increase bd_ram_size and number of rx descriptors.
> 
> Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>

Dave

Please drop this patch as it is not working on AM437x platform. Will
send a v2 after fixing it.

Regards
Mugunthan V N