From a20fafb92bd84b9ab585ef4743339c96865cada2 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Wed, 8 Jul 2020 14:25:37 +0200 Subject: net: dsa: rtl8366rb: Support the CPU DSA tag This activates the support to use the CPU tag to properly direct ingress traffic to the right port. Bit 15 in register RTL8368RB_CPU_CTRL_REG can be set to 1 to disable the insertion of the CPU tag which is what the code currently does. The bit 15 define calls this setting RTL8368RB_CPU_INSTAG which is confusing since the inverse meaning is implied: programmers may think that setting this bit to 1 will *enable* inserting the tag rather than disabling it, so rename this setting in bit 15 to RTL8368RB_CPU_NO_TAG which is more to the point. After this e.g. ping works out-of-the-box with the RTL8366RB. Cc: DENG Qingfang Cc: Mauri Sandberg Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: Linus Walleij Signed-off-by: David S. Miller --- drivers/net/dsa/rtl8366rb.c | 31 ++++++++----------------------- 1 file changed, 8 insertions(+), 23 deletions(-) (limited to 'drivers/net/dsa/rtl8366rb.c') diff --git a/drivers/net/dsa/rtl8366rb.c b/drivers/net/dsa/rtl8366rb.c index fd1977590cb4..48f1ff746799 100644 --- a/drivers/net/dsa/rtl8366rb.c +++ b/drivers/net/dsa/rtl8366rb.c @@ -109,8 +109,8 @@ /* CPU port control reg */ #define RTL8368RB_CPU_CTRL_REG 0x0061 #define RTL8368RB_CPU_PORTS_MSK 0x00FF -/* Enables inserting custom tag length/type 0x8899 */ -#define RTL8368RB_CPU_INSTAG BIT(15) +/* Disables inserting custom tag length/type 0x8899 */ +#define RTL8368RB_CPU_NO_TAG BIT(15) #define RTL8366RB_SMAR0 0x0070 /* bits 0..15 */ #define RTL8366RB_SMAR1 0x0071 /* bits 16..31 */ @@ -844,16 +844,14 @@ static int rtl8366rb_setup(struct dsa_switch *ds) if (ret) return ret; - /* Enable CPU port and enable inserting CPU tag + /* Enable CPU port with custom DSA tag 8899. * - * Disabling RTL8368RB_CPU_INSTAG here will change the behaviour - * of the switch totally and it will start talking Realtek RRCP - * internally. It is probably possible to experiment with this, - * but then the kernel needs to understand and handle RRCP first. + * If you set RTL8368RB_CPU_NO_TAG (bit 15) in this registers + * the custom tag is turned off. */ ret = regmap_update_bits(smi->map, RTL8368RB_CPU_CTRL_REG, 0xFFFF, - RTL8368RB_CPU_INSTAG | BIT(smi->cpu_port)); + BIT(smi->cpu_port)); if (ret) return ret; @@ -967,21 +965,8 @@ static enum dsa_tag_protocol rtl8366_get_tag_protocol(struct dsa_switch *ds, int port, enum dsa_tag_protocol mp) { - /* For now, the RTL switches are handled without any custom tags. - * - * It is possible to turn on "custom tags" by removing the - * RTL8368RB_CPU_INSTAG flag when enabling the port but what it - * does is unfamiliar to DSA: ethernet frames of type 8899, the Realtek - * Remote Control Protocol (RRCP) start to appear on the CPU port of - * the device. So this is not the ordinary few extra bytes in the - * frame. Instead it appears that the switch starts to talk Realtek - * RRCP internally which means a pretty complex RRCP implementation - * decoding and responding the RRCP protocol is needed to exploit this. - * - * The OpenRRCP project (dormant since 2009) have reverse-egineered - * parts of the protocol. - */ - return DSA_TAG_PROTO_NONE; + /* This switch uses the 4 byte protocol A Realtek DSA tag */ + return DSA_TAG_PROTO_RTL4_A; } static void rtl8366rb_adjust_link(struct dsa_switch *ds, int port, -- cgit v1.2.3