[PATCH v4] thunderbolt: Add quirk to disable CLx

[PATCH v4] thunderbolt: Add quirk to disable CLx

[Sanjay R Mehta]

From: Sanjay R Mehta <sanju.mehta@amd.com>

Add QUIRK_NO_CLX to disable the CLx state for hardware which
doesn't supports it.

AMD Yellow Carp and Pink Sardine don't support CLx state,
hence disabling it using QUIRK_NO_CLX.

Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
---
 drivers/thunderbolt/quirks.c | 12 ++++++++++++
 drivers/thunderbolt/tb.h     | 11 ++++++++---
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/thunderbolt/quirks.c b/drivers/thunderbolt/quirks.c
index b5f2ec7..03cd390 100644
--- a/drivers/thunderbolt/quirks.c
+++ b/drivers/thunderbolt/quirks.c
@@ -20,6 +20,11 @@ static void quirk_dp_credit_allocation(struct tb_switch *sw)
 	}
 }
 
+static void quirk_clx_disable(struct tb_switch *sw)
+{
+	sw->quirks |= QUIRK_NO_CLX;
+}
+
 struct tb_quirk {
 	u16 hw_vendor_id;
 	u16 hw_device_id;
@@ -37,6 +42,13 @@ static const struct tb_quirk tb_quirks[] = {
 	 * DP buffers.
 	 */
 	{ 0x8087, 0x0b26, 0x0000, 0x0000, quirk_dp_credit_allocation },
+	/*
+	 * CLx is not supported on AMD USB4 Yellow Carp and Pink Sardine platforms.
+	 */
+	{ 0x0438, 0x0208, 0x0000, 0x0000, quirk_clx_disable },
+	{ 0x0438, 0x0209, 0x0000, 0x0000, quirk_clx_disable },
+	{ 0x0438, 0x020a, 0x0000, 0x0000, quirk_clx_disable },
+	{ 0x0438, 0x020b, 0x0000, 0x0000, quirk_clx_disable },
 };
 
 /**
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index f978697..206759a 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -23,6 +23,11 @@
 #define NVM_MAX_SIZE		SZ_512K
 #define NVM_DATA_DWORDS		16
 
+/* Keep link controller awake during update */
+#define QUIRK_FORCE_POWER_LINK_CONTROLLER		BIT(0)
+/* Disable CLx if not supported */
+#define QUIRK_NO_CLX					BIT(1)
+
 /**
  * struct tb_nvm - Structure holding NVM information
  * @dev: Owner of the NVM
@@ -997,6 +1002,9 @@ static inline bool tb_switch_is_clx_enabled(const struct tb_switch *sw,
  */
 static inline bool tb_switch_is_clx_supported(const struct tb_switch *sw)
 {
+	if (sw->quirks & QUIRK_NO_CLX)
+		return false;
+
 	return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
 }
 
@@ -1254,9 +1262,6 @@ struct usb4_port *usb4_port_device_add(struct tb_port *port);
 void usb4_port_device_remove(struct usb4_port *usb4);
 int usb4_port_device_resume(struct usb4_port *usb4);
 
-/* Keep link controller awake during update */
-#define QUIRK_FORCE_POWER_LINK_CONTROLLER		BIT(0)
-
 void tb_check_quirks(struct tb_switch *sw);
 
 #ifdef CONFIG_ACPI
-- 
2.7.4

Re: [PATCH v4] thunderbolt: Add quirk to disable CLx

[Mika Westerberg]

Hi,

On Tue, Feb 14, 2023 at 01:13:50PM -0600, Sanjay R Mehta wrote:
> From: Sanjay R Mehta <sanju.mehta@amd.com>
> 
> Add QUIRK_NO_CLX to disable the CLx state for hardware which
> doesn't supports it.
> 
> AMD Yellow Carp and Pink Sardine don't support CLx state,
> hence disabling it using QUIRK_NO_CLX.
> 
> Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
> Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>

This looks good, thanks! I will pick this up after the merge window is
over as I already sent out my PR for v6.3-rc1.

Re: [PATCH v4] thunderbolt: Add quirk to disable CLx

[Mika Westerberg]

On Tue, Feb 14, 2023 at 01:13:50PM -0600, Sanjay R Mehta wrote:
> From: Sanjay R Mehta <sanju.mehta@amd.com>
> 
> Add QUIRK_NO_CLX to disable the CLx state for hardware which
> doesn't supports it.
> 
> AMD Yellow Carp and Pink Sardine don't support CLx state,
> hence disabling it using QUIRK_NO_CLX.
> 
> Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
> Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>

I added debug log when the quirk is run and applied to
thunderbolt.git/fixes, thanks!