If vpcie3v3 is available, we could provide these information
via RC's configure register to make EP able to know the power
limit.
Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---
Changes in v2:
- rebase the code since it isn't cleanly applied after Bjorn's cleanup
drivers/pci/host/pcie-rockchip.c | 40 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)
diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c
index b3548d0..75b6bbf 100644
--- a/drivers/pci/host/pcie-rockchip.c
+++ b/drivers/pci/host/pcie-rockchip.c
@@ -135,6 +135,10 @@
#define PCIE_RC_CONFIG_VENDOR (PCIE_RC_CONFIG_BASE + 0x00)
#define PCIE_RC_CONFIG_RID_CCR (PCIE_RC_CONFIG_BASE + 0x08)
#define PCIE_RC_CONFIG_SCC_SHIFT 16
+#define PCIE_RC_CONFIG_DCR (PCIE_RC_CONFIG_BASE + 0xc4)
+#define PCIE_RC_CONFIG_DCR_CSPL_SHIFT 18
+#define PCIE_RC_CONFIG_DCR_CSPL_LIMIT 0xff
+#define PCIE_RC_CONFIG_DCR_CPLS_SHIFT 26
#define PCIE_RC_CONFIG_LCS (PCIE_RC_CONFIG_BASE + 0xd0)
#define PCIE_RC_CONFIG_LCS_RETRAIN_LINK BIT(5)
#define PCIE_RC_CONFIG_LCS_LBMIE BIT(10)
@@ -394,6 +398,40 @@ static struct pci_ops rockchip_pcie_ops = {
.write = rockchip_pcie_wr_conf,
};
+static void rockchip_pcie_set_power_limit(struct rockchip_pcie *rockchip)
+{
+ u32 status, curr, scale, power;
+
+ if (IS_ERR(rockchip->vpcie3v3))
+ return;
+
+ /*
+ * Set RC's captured slot power limit and scale if
+ * vpcie3v3 available. The default values are both zero
+ * which means the software should set these two according
+ * to the actual power supply.
+ */
+ curr = regulator_get_current_limit(rockchip->vpcie3v3);
+ if (curr > 0) {
+ scale = 3; /* 0.001x */
+ curr = curr / 1000; /* convert to mA */
+ power = (curr * 3300) / 1000; /* milliwatt */
+ while (power > PCIE_RC_CONFIG_DCR_CSPL_LIMIT) {
+ if (!scale) {
+ dev_warn(rockchip->dev, "invalid power supply\n");
+ return;
+ }
+ scale--;
+ power = power / 10;
+ }
+
+ status = rockchip_readl(rockchip, PCIE_RC_CONFIG_DCR);
+ status |= (power << PCIE_RC_CONFIG_DCR_CSPL_SHIFT) |
+ (scale << PCIE_RC_CONFIG_DCR_CPLS_SHIFT);
+ rockchip_writel(rockchip, PCIE_RC_CONFIG_DCR, status);
+ }
+}
+
/**
* rockchip_pcie_init_port - Initialize hardware
* @rockchip: PCIe port information
@@ -494,6 +532,8 @@ static int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
(PCIE_CORE_CTRL_PLC1_FTS_CNT << PCIE_CORE_CTRL_PLC1_FTS_SHIFT);
rockchip_writel(rockchip, PCIE_CORE_CTRL_PLC1, status);
+ rockchip_pcie_set_power_limit(rockchip);
+
/* Enable Gen1 training */
rockchip_writel(rockchip, PCIE_CLIENT_CONFIG,
PCIE_CLIENT_LINK_TRAIN_ENABLE);
--
2.3.7
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
