thunderbolt: Limit USB3 bandwidth of certain Intel USB4 host routers

[ Upstream commit f0a57dd33b ]

Current Intel USB4 host routers have hardware limitation that the USB3
bandwidth cannot go higher than 16376 Mb/s. Work this around by adding a
new quirk that limits the bandwidth for the affected host routers.

Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Gil Fine 2023-01-31 13:04:52 +02:00 committed by Greg Kroah-Hartman
parent 3b29299e5f
commit eddee1c229
3 changed files with 49 additions and 2 deletions

View File

@ -26,6 +26,19 @@ static void quirk_clx_disable(struct tb_switch *sw)
tb_sw_dbg(sw, "disabling CL states\n");
}
static void quirk_usb3_maximum_bandwidth(struct tb_switch *sw)
{
struct tb_port *port;
tb_switch_for_each_port(sw, port) {
if (!tb_port_is_usb3_down(port))
continue;
port->max_bw = 16376;
tb_port_dbg(port, "USB3 maximum bandwidth limited to %u Mb/s\n",
port->max_bw);
}
}
struct tb_quirk {
u16 hw_vendor_id;
u16 hw_device_id;
@ -43,6 +56,24 @@ static const struct tb_quirk tb_quirks[] = {
* DP buffers.
*/
{ 0x8087, 0x0b26, 0x0000, 0x0000, quirk_dp_credit_allocation },
/*
* Limit the maximum USB3 bandwidth for the following Intel USB4
* host routers due to a hardware issue.
*/
{ 0x8087, PCI_DEVICE_ID_INTEL_ADL_NHI0, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_ADL_NHI1, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_RPL_NHI0, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_RPL_NHI1, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_MTL_M_NHI0, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_MTL_P_NHI0, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
{ 0x8087, PCI_DEVICE_ID_INTEL_MTL_P_NHI1, 0x0000, 0x0000,
quirk_usb3_maximum_bandwidth },
/*
* CLx is not supported on AMD USB4 Yellow Carp and Pink Sardine platforms.
*/

View File

@ -252,6 +252,8 @@ struct tb_switch {
* @ctl_credits: Buffers reserved for control path
* @dma_credits: Number of credits allocated for DMA tunneling for all
* DMA paths through this port.
* @max_bw: Maximum possible bandwidth through this adapter if set to
* non-zero.
*
* In USB4 terminology this structure represents an adapter (protocol or
* lane adapter).
@ -277,6 +279,7 @@ struct tb_port {
unsigned int total_credits;
unsigned int ctl_credits;
unsigned int dma_credits;
unsigned int max_bw;
};
/**

View File

@ -1865,6 +1865,15 @@ int usb4_port_retimer_nvm_read(struct tb_port *port, u8 index,
usb4_port_retimer_nvm_read_block, &info);
}
static inline unsigned int
usb4_usb3_port_max_bandwidth(const struct tb_port *port, unsigned int bw)
{
/* Take the possible bandwidth limitation into account */
if (port->max_bw)
return min(bw, port->max_bw);
return bw;
}
/**
* usb4_usb3_port_max_link_rate() - Maximum support USB3 link rate
* @port: USB3 adapter port
@ -1886,7 +1895,9 @@ int usb4_usb3_port_max_link_rate(struct tb_port *port)
return ret;
lr = (val & ADP_USB3_CS_4_MSLR_MASK) >> ADP_USB3_CS_4_MSLR_SHIFT;
return lr == ADP_USB3_CS_4_MSLR_20G ? 20000 : 10000;
ret = lr == ADP_USB3_CS_4_MSLR_20G ? 20000 : 10000;
return usb4_usb3_port_max_bandwidth(port, ret);
}
/**
@ -1913,7 +1924,9 @@ int usb4_usb3_port_actual_link_rate(struct tb_port *port)
return 0;
lr = val & ADP_USB3_CS_4_ALR_MASK;
return lr == ADP_USB3_CS_4_ALR_20G ? 20000 : 10000;
ret = lr == ADP_USB3_CS_4_ALR_20G ? 20000 : 10000;
return usb4_usb3_port_max_bandwidth(port, ret);
}
static int usb4_usb3_port_cm_request(struct tb_port *port, bool request)