diff mbox series

[net-next,v3,2/2] net: stmmac: qcom-ethqos: enable SGMII loopback during DMA reset on sa8775p-ride-r3

Message ID 20240703181500.28491-3-brgl@bgdev.pl (mailing list archive)
State Accepted
Commit 3c466d6537b99f801b3f68af3d8124d4312437a0
Delegated to: Netdev Maintainers
Headers show
Series net: stmmac: qcom-ethqos: enable 2.5G ethernet on sa8775p-ride | expand

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netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 839 this patch: 839
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 7 maintainers not CCed: alexandre.torgue@foss.st.com mcoquelin.stm32@gmail.com linux-arm-msm@vger.kernel.org linux-arm-kernel@lists.infradead.org joabreu@synopsys.com vkoul@kernel.org linux-stm32@st-md-mailman.stormreply.com
netdev/build_clang success Errors and warnings before: 846 this patch: 846
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 846 this patch: 846
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 73 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-07-05--06-00 (tests: 695)

Commit Message

Bartosz Golaszewski July 3, 2024, 6:14 p.m. UTC 
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

On sa8775p-ride-r3 the RX clocks from the AQR115C PHY are not available at
the time of the DMA reset. We can however extract the RX clock from the
internal SERDES block. Once the link is up, we can revert to the
previous state.

The AQR115C PHY doesn't support in-band signalling so we can count on
getting the link up notification and safely reuse existing callbacks
which are already used by another HW quirk workaround which enables the
functional clock to avoid a DMA reset due to timeout.

Only enable loopback on revision 3 of the board - check the phy_mode to
make sure.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 .../stmicro/stmmac/dwmac-qcom-ethqos.c        | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

Comments

Andrew Lunn July 8, 2024, 1:25 p.m. UTC | #1 
On Wed, Jul 03, 2024 at 08:14:59PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> On sa8775p-ride-r3 the RX clocks from the AQR115C PHY are not available at
> the time of the DMA reset. We can however extract the RX clock from the
> internal SERDES block. Once the link is up, we can revert to the
> previous state.
> 
> The AQR115C PHY doesn't support in-band signalling so we can count on
> getting the link up notification and safely reuse existing callbacks
> which are already used by another HW quirk workaround which enables the
> functional clock to avoid a DMA reset due to timeout.
> 
> Only enable loopback on revision 3 of the board - check the phy_mode to
> make sure.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew
diff mbox series

Patch

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index 91fe57a3e59e..e46cbacc627d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -21,6 +21,7 @@ 
 #define RGMII_IO_MACRO_CONFIG2		0x1C
 #define RGMII_IO_MACRO_DEBUG1		0x20
 #define EMAC_SYSTEM_LOW_POWER_DEBUG	0x28
+#define EMAC_WRAPPER_SGMII_PHY_CNTRL1	0xf4
 
 /* RGMII_IO_MACRO_CONFIG fields */
 #define RGMII_CONFIG_FUNC_CLK_EN		BIT(30)
@@ -79,6 +80,9 @@ 
 #define ETHQOS_MAC_CTRL_SPEED_MODE		BIT(14)
 #define ETHQOS_MAC_CTRL_PORT_SEL		BIT(15)
 
+/* EMAC_WRAPPER_SGMII_PHY_CNTRL1 bits */
+#define SGMII_PHY_CNTRL1_SGMII_TX_TO_RX_LOOPBACK_EN	BIT(3)
+
 #define SGMII_10M_RX_CLK_DVDR			0x31
 
 struct ethqos_emac_por {
@@ -95,6 +99,7 @@  struct ethqos_emac_driver_data {
 	bool has_integrated_pcs;
 	u32 dma_addr_width;
 	struct dwmac4_addrs dwmac4_addrs;
+	bool needs_sgmii_loopback;
 };
 
 struct qcom_ethqos {
@@ -114,6 +119,7 @@  struct qcom_ethqos {
 	unsigned int num_por;
 	bool rgmii_config_loopback_en;
 	bool has_emac_ge_3;
+	bool needs_sgmii_loopback;
 };
 
 static int rgmii_readl(struct qcom_ethqos *ethqos, unsigned int offset)
@@ -191,8 +197,22 @@  ethqos_update_link_clk(struct qcom_ethqos *ethqos, unsigned int speed)
 	clk_set_rate(ethqos->link_clk, ethqos->link_clk_rate);
 }
 
+static void
+qcom_ethqos_set_sgmii_loopback(struct qcom_ethqos *ethqos, bool enable)
+{
+	if (!ethqos->needs_sgmii_loopback ||
+	    ethqos->phy_mode != PHY_INTERFACE_MODE_2500BASEX)
+		return;
+
+	rgmii_updatel(ethqos,
+		      SGMII_PHY_CNTRL1_SGMII_TX_TO_RX_LOOPBACK_EN,
+		      enable ? SGMII_PHY_CNTRL1_SGMII_TX_TO_RX_LOOPBACK_EN : 0,
+		      EMAC_WRAPPER_SGMII_PHY_CNTRL1);
+}
+
 static void ethqos_set_func_clk_en(struct qcom_ethqos *ethqos)
 {
+	qcom_ethqos_set_sgmii_loopback(ethqos, true);
 	rgmii_updatel(ethqos, RGMII_CONFIG_FUNC_CLK_EN,
 		      RGMII_CONFIG_FUNC_CLK_EN, RGMII_IO_MACRO_CONFIG);
 }
@@ -277,6 +297,7 @@  static const struct ethqos_emac_driver_data emac_v4_0_0_data = {
 	.has_emac_ge_3 = true,
 	.link_clk_name = "phyaux",
 	.has_integrated_pcs = true,
+	.needs_sgmii_loopback = true,
 	.dma_addr_width = 36,
 	.dwmac4_addrs = {
 		.dma_chan = 0x00008100,
@@ -682,6 +703,7 @@  static void ethqos_fix_mac_speed(void *priv, unsigned int speed, unsigned int mo
 {
 	struct qcom_ethqos *ethqos = priv;
 
+	qcom_ethqos_set_sgmii_loopback(ethqos, false);
 	ethqos->speed = speed;
 	ethqos_update_link_clk(ethqos, speed);
 	ethqos_configure(ethqos);
@@ -820,6 +842,7 @@  static int qcom_ethqos_probe(struct platform_device *pdev)
 	ethqos->num_por = data->num_por;
 	ethqos->rgmii_config_loopback_en = data->rgmii_config_loopback_en;
 	ethqos->has_emac_ge_3 = data->has_emac_ge_3;
+	ethqos->needs_sgmii_loopback = data->needs_sgmii_loopback;
 
 	ethqos->link_clk = devm_clk_get(dev, data->link_clk_name ?: "rgmii");
 	if (IS_ERR(ethqos->link_clk))