[PATCH 1/1] r8169: add module parameter aspm_en_force

[Crag Wang]

ASPM is disabled by default and is enabled if the chip register is
pre-configured, as explained in #c217ab7.

A module parameter is being added to the driver to allow users to
override the default setting. This allows users to opt in and forcefully
enable or disable ASPM power-saving mode.

-1: default unset
 0: ASPM disabled forcefully
 1: ASPM enabled forcefully

Signed-off-by: Crag Wang <crag0715@xxxxxxxxx>
---
 drivers/net/ethernet/realtek/r8169_main.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 53e541ddb439..161b2f2edf52 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -35,6 +35,10 @@
 #include "r8169.h"
 #include "r8169_firmware.h"
 
+static int aspm_en_force = -1;
+module_param(aspm_en_force, int, 0444);
+MODULE_PARM_DESC(aspm_en_force, "r8169: An integer, set 1 to force enable link ASPM");
+
 #define FIRMWARE_8168D_1	"rtl_nic/rtl8168d-1.fw"
 #define FIRMWARE_8168D_2	"rtl_nic/rtl8168d-2.fw"
 #define FIRMWARE_8168E_1	"rtl_nic/rtl8168e-1.fw"
@@ -5398,6 +5402,14 @@ static void rtl_init_mac_address(struct rtl8169_private *tp)
 /* register is set if system vendor successfully tested ASPM 1.2 */
 static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
 {
+	if (aspm_en_force == 0) {
+		dev_info(tp_to_dev(tp), "ASPM disabled forcefully");
+		return false;
+	} else if (aspm_en_force > 0) {
+		dev_info(tp_to_dev(tp), "ASPM enabled forcefully");
+		return true;
+	}
+
 	if (tp->mac_version >= RTL_GIGA_MAC_VER_61 &&
 	    r8168_mac_ocp_read(tp, 0xc0b2) & 0xf)
 		return true;
-- 
2.43.0