diff options
| author | Shawn Lin <shawn.lin@rock-chips.com> | 2016-12-07 15:05:59 -0600 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2016-12-07 15:05:59 -0600 |
| commit | f2fb5b8f2a0cb67ba4535eb08d9cfb301ac92429 (patch) | |
| tree | ab5612c901646171d9b609884d5f1acccad25e60 /drivers/pci | |
| parent | 45e9320f3a4ef9588ee50a2eb1891c4bfdbb07df (diff) | |
| download | linux-f2fb5b8f2a0cb67ba4535eb08d9cfb301ac92429.tar.gz | |
PCI: rockchip: Specify the link capability
rk3399 supports PCIe 2.x link speeds marginally at best, and on some
boards, the link won't train at 5 GT/s at all. Rather than sacrifice 500ms
waiting for training that will never happen, let's use the helper function,
of_pci_get_max_link_speed(), to get the max link speed from DT and specify
link capability.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/host/pcie-rockchip.c | 60 |
1 files changed, 37 insertions, 23 deletions
diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c index f641a4e6f605..13e0dd6097a4 100644 --- a/drivers/pci/host/pcie-rockchip.c +++ b/drivers/pci/host/pcie-rockchip.c @@ -53,6 +53,7 @@ #define PCIE_CLIENT_ARI_ENABLE HIWORD_UPDATE_BIT(0x0008) #define PCIE_CLIENT_CONF_LANE_NUM(x) HIWORD_UPDATE(0x0030, ENCODE_LANES(x)) #define PCIE_CLIENT_MODE_RC HIWORD_UPDATE_BIT(0x0040) +#define PCIE_CLIENT_GEN_SEL_1 HIWORD_UPDATE(0x0080, 0) #define PCIE_CLIENT_GEN_SEL_2 HIWORD_UPDATE_BIT(0x0080) #define PCIE_CLIENT_BASIC_STATUS1 (PCIE_CLIENT_BASE + 0x48) #define PCIE_CLIENT_LINK_STATUS_UP 0x00300000 @@ -208,6 +209,7 @@ struct rockchip_pcie { struct gpio_desc *ep_gpio; u32 lanes; u8 root_bus_nr; + int link_gen; struct device *dev; struct irq_domain *irq_domain; }; @@ -518,14 +520,20 @@ static int rockchip_pcie_init_port(struct rockchip_pcie *rockchip) return err; } + if (rockchip->link_gen == 2) + rockchip_pcie_write(rockchip, PCIE_CLIENT_GEN_SEL_2, + PCIE_CLIENT_CONFIG); + else + rockchip_pcie_write(rockchip, PCIE_CLIENT_GEN_SEL_1, + PCIE_CLIENT_CONFIG); + rockchip_pcie_write(rockchip, PCIE_CLIENT_CONF_ENABLE | PCIE_CLIENT_LINK_TRAIN_ENABLE | PCIE_CLIENT_ARI_ENABLE | PCIE_CLIENT_CONF_LANE_NUM(rockchip->lanes) | - PCIE_CLIENT_MODE_RC | - PCIE_CLIENT_GEN_SEL_2, - PCIE_CLIENT_CONFIG); + PCIE_CLIENT_MODE_RC, + PCIE_CLIENT_CONFIG); err = phy_power_on(rockchip->phy); if (err) { @@ -609,29 +617,31 @@ static int rockchip_pcie_init_port(struct rockchip_pcie *rockchip) msleep(20); } - /* - * Enable retrain for gen2. This should be configured only after - * gen1 finished. - */ - status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS); - status |= PCIE_RC_CONFIG_LCS_RETRAIN_LINK; - rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS); + if (rockchip->link_gen == 2) { + /* + * Enable retrain for gen2. This should be configured only after + * gen1 finished. + */ + status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS); + status |= PCIE_RC_CONFIG_LCS_RETRAIN_LINK; + rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS); + + timeout = jiffies + msecs_to_jiffies(500); + for (;;) { + status = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL); + if ((status & PCIE_CORE_PL_CONF_SPEED_MASK) == + PCIE_CORE_PL_CONF_SPEED_5G) { + dev_dbg(dev, "PCIe link training gen2 pass!\n"); + break; + } - timeout = jiffies + msecs_to_jiffies(500); - for (;;) { - status = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL); - if ((status & PCIE_CORE_PL_CONF_SPEED_MASK) == - PCIE_CORE_PL_CONF_SPEED_5G) { - dev_dbg(dev, "PCIe link training gen2 pass!\n"); - break; - } + if (time_after(jiffies, timeout)) { + dev_dbg(dev, "PCIe link training gen2 timeout, fall back to gen1!\n"); + break; + } - if (time_after(jiffies, timeout)) { - dev_dbg(dev, "PCIe link training gen2 timeout, fall back to gen1!\n"); - break; + msleep(20); } - - msleep(20); } /* Check the final link width from negotiated lane counter from MGMT */ @@ -840,6 +850,10 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip) rockchip->lanes = 1; } + rockchip->link_gen = of_pci_get_max_link_speed(node); + if (rockchip->link_gen < 0 || rockchip->link_gen > 2) + rockchip->link_gen = 2; + rockchip->core_rst = devm_reset_control_get(dev, "core"); if (IS_ERR(rockchip->core_rst)) { if (PTR_ERR(rockchip->core_rst) != -EPROBE_DEFER) |