diff options
Diffstat (limited to 'drivers/thunderbolt/usb4.c')
| -rw-r--r-- | drivers/thunderbolt/usb4.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index b56af7b0a093..edab8ea63c0b 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -36,6 +36,20 @@ enum usb4_sb_target { #define USB4_NVM_SECTOR_SIZE_MASK GENMASK(23, 0) +#define USB4_BA_LENGTH_MASK GENMASK(7, 0) +#define USB4_BA_INDEX_MASK GENMASK(15, 0) + +enum usb4_ba_index { + USB4_BA_MAX_USB3 = 0x1, + USB4_BA_MIN_DP_AUX = 0x2, + USB4_BA_MIN_DP_MAIN = 0x3, + USB4_BA_MAX_PCIE = 0x4, + USB4_BA_MAX_HI = 0x5, +}; + +#define USB4_BA_VALUE_MASK GENMASK(31, 16) +#define USB4_BA_VALUE_SHIFT 16 + static int usb4_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit, u32 value, int timeout_msec) { @@ -670,6 +684,147 @@ int usb4_switch_nvm_authenticate_status(struct tb_switch *sw, u32 *status) } /** + * usb4_switch_credits_init() - Read buffer allocation parameters + * @sw: USB4 router + * + * Reads @sw buffer allocation parameters and initializes @sw buffer + * allocation fields accordingly. Specifically @sw->credits_allocation + * is set to %true if these parameters can be used in tunneling. + * + * Returns %0 on success and negative errno otherwise. + */ +int usb4_switch_credits_init(struct tb_switch *sw) +{ + int max_usb3, min_dp_aux, min_dp_main, max_pcie, max_dma; + int ret, length, i, nports; + const struct tb_port *port; + u32 data[NVM_DATA_DWORDS]; + u32 metadata = 0; + u8 status = 0; + + memset(data, 0, sizeof(data)); + ret = usb4_switch_op_data(sw, USB4_SWITCH_OP_BUFFER_ALLOC, &metadata, + &status, NULL, 0, data, ARRAY_SIZE(data)); + if (ret) + return ret; + if (status) + return -EIO; + + length = metadata & USB4_BA_LENGTH_MASK; + if (WARN_ON(length > ARRAY_SIZE(data))) + return -EMSGSIZE; + + max_usb3 = -1; + min_dp_aux = -1; + min_dp_main = -1; + max_pcie = -1; + max_dma = -1; + + tb_sw_dbg(sw, "credit allocation parameters:\n"); + + for (i = 0; i < length; i++) { + u16 index, value; + + index = data[i] & USB4_BA_INDEX_MASK; + value = (data[i] & USB4_BA_VALUE_MASK) >> USB4_BA_VALUE_SHIFT; + + switch (index) { + case USB4_BA_MAX_USB3: + tb_sw_dbg(sw, " USB3: %u\n", value); + max_usb3 = value; + break; + case USB4_BA_MIN_DP_AUX: + tb_sw_dbg(sw, " DP AUX: %u\n", value); + min_dp_aux = value; + break; + case USB4_BA_MIN_DP_MAIN: + tb_sw_dbg(sw, " DP main: %u\n", value); + min_dp_main = value; + break; + case USB4_BA_MAX_PCIE: + tb_sw_dbg(sw, " PCIe: %u\n", value); + max_pcie = value; + break; + case USB4_BA_MAX_HI: + tb_sw_dbg(sw, " DMA: %u\n", value); + max_dma = value; + break; + default: + tb_sw_dbg(sw, " unknown credit allocation index %#x, skipping\n", + index); + break; + } + } + + /* + * Validate the buffer allocation preferences. If we find + * issues, log a warning and fall back using the hard-coded + * values. + */ + + /* Host router must report baMaxHI */ + if (!tb_route(sw) && max_dma < 0) { + tb_sw_warn(sw, "host router is missing baMaxHI\n"); + goto err_invalid; + } + + nports = 0; + tb_switch_for_each_port(sw, port) { + if (tb_port_is_null(port)) + nports++; + } + + /* Must have DP buffer allocation (multiple USB4 ports) */ + if (nports > 2 && (min_dp_aux < 0 || min_dp_main < 0)) { + tb_sw_warn(sw, "multiple USB4 ports require baMinDPaux/baMinDPmain\n"); + goto err_invalid; + } + + tb_switch_for_each_port(sw, port) { + if (tb_port_is_dpout(port) && min_dp_main < 0) { + tb_sw_warn(sw, "missing baMinDPmain"); + goto err_invalid; + } + if ((tb_port_is_dpin(port) || tb_port_is_dpout(port)) && + min_dp_aux < 0) { + tb_sw_warn(sw, "missing baMinDPaux"); + goto err_invalid; + } + if ((tb_port_is_usb3_down(port) || tb_port_is_usb3_up(port)) && + max_usb3 < 0) { + tb_sw_warn(sw, "missing baMaxUSB3"); + goto err_invalid; + } + if ((tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) && + max_pcie < 0) { + tb_sw_warn(sw, "missing baMaxPCIe"); + goto err_invalid; + } + } + + /* + * Buffer allocation passed the validation so we can use it in + * path creation. + */ + sw->credit_allocation = true; + if (max_usb3 > 0) + sw->max_usb3_credits = max_usb3; + if (min_dp_aux > 0) + sw->min_dp_aux_credits = min_dp_aux; + if (min_dp_main > 0) + sw->min_dp_main_credits = min_dp_main; + if (max_pcie > 0) + sw->max_pcie_credits = max_pcie; + if (max_dma > 0) + sw->max_dma_credits = max_dma; + + return 0; + +err_invalid: + return -EINVAL; +} + +/** * usb4_switch_query_dp_resource() - Query availability of DP IN resource * @sw: USB4 router * @in: DP IN adapter |