[net-next PATCH 2/2 v5] net: dsa: rtl8366rb: Support the CPU DSA tag
From: Linus Walleij <hidden>
Date: 2020-07-07 21:16:29
Subsystem:
networking drivers, networking [dsa], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Vladimir Oltean, Linus Torvalds
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 <dqfext@gmail.com> Cc: Mauri Sandberg <redacted> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Linus Walleij <redacted> --- ChangeLog v4->v5: - Split tagging support from the VLAN fix-ups. ChangeLog v3->v4: - Resend with the rest ChangeLog v2->v3: - Fix up the commit message. - Collect Andrew's review tag. ChangeLog v1->v2: - Update the commit message to explain why we are renaming bit 15 in RTL8368RB_CPU_CTRL_REG. --- drivers/net/dsa/Kconfig | 1 + drivers/net/dsa/rtl8366rb.c | 31 ++++++++----------------------- 2 files changed, 9 insertions(+), 23 deletions(-)
diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index d0024cb30a7b..468b3c4273c5 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig@@ -70,6 +70,7 @@ config NET_DSA_QCA8K config NET_DSA_REALTEK_SMI tristate "Realtek SMI Ethernet switch family support" depends on NET_DSA + select NET_DSA_TAG_RTL4_A select FIXED_PHY select IRQ_DOMAIN select REALTEK_PHY
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,
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2.26.2