[PATCH V2 6/8] brcmfmac: update 43012 F2 watermark setting to fix DMA Error during UDP RX Traffic

[Chi-Hsien Lin <Chi-Hsien.Lin@cypress.com>]

From: Naveen Gupta <naveen.gupta@cypress.com>

The number of words that the read FIFO has to contain except
the end of frame before sends data back to the host.
Max watermark = (512B - 2* (BurstLength))/4 =
(512 - 128)/4 = 384/4 = 0x60
so if burst length (i.e. BurstLength = 64) is increased,
watermark has to be reduced. This is the optimal setting for this chip.

Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Naveen Gupta <naveen.gupta@cypress.com>
Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
index 7707b0169c21..e1708e297d07 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
@@ -52,6 +52,7 @@
 /* watermark expressed in number of words */
 #define DEFAULT_F2_WATERMARK    0x8
 #define CY_4373_F2_WATERMARK    0x40
+#define CY_43012_F2_WATERMARK    0x60
 
 #ifdef DEBUG
 
@@ -4173,6 +4174,17 @@ static void brcmf_sdio_firmware_callback(struct device *dev, int err,
 					   CY_4373_F2_WATERMARK |
 					   SBSDIO_MESBUSYCTRL_ENAB, &err);
 			break;
+		case SDIO_DEVICE_ID_CYPRESS_43012:
+			brcmf_dbg(INFO, "set F2 watermark to 0x%x*4 bytes\n",
+				  CY_43012_F2_WATERMARK);
+			brcmf_sdiod_writeb(sdiod, SBSDIO_WATERMARK,
+					   CY_43012_F2_WATERMARK, &err);
+			devctl = brcmf_sdiod_readb(sdiod, SBSDIO_DEVICE_CTL,
+						   &err);
+			devctl |= SBSDIO_DEVCTL_F2WM_ENAB;
+			brcmf_sdiod_writeb(sdiod, SBSDIO_DEVICE_CTL, devctl,
+					   &err);
+			break;
 		default:
 			brcmf_sdiod_writeb(sdiod, SBSDIO_WATERMARK,
 					   DEFAULT_F2_WATERMARK, &err);
-- 
2.1.0