leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

PCI: tegra: Add support to enable slot regulators

Browse Source 
Add support to get regulator information of 3.3V and 12V supplies of a PCIe
slot from the respective controller's device-tree node and enable those
supplies. This is required in platforms like p2972-0000 where the supplies
to x16 slot owned by C5 controller need to be enabled before attempting to
enumerate the devices.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Thierry Reding <treding@nvidia.com>
This commit is contained in:
Vidya Sagar 2019-09-05 16:15:51 +05:30 committed by Bjorn Helgaas
parent f4ff4faf89
commit 0a901f2130
1 changed files with 83 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

83
drivers/pci/controller/dwc/pcie-tegra194.c
View File

@ -278,6 +278,8 @@ struct tegra_pcie_dw {
u32 aspm_l0s_enter_lat;
struct regulator *pex_ctl_supply;
struct regulator *slot_ctl_3v3;
struct regulator *slot_ctl_12v;
unsigned int phy_count;
struct phy **phys;
@ -1055,6 +1057,73 @@ static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
}
}
static int tegra_pcie_get_slot_regulators(struct tegra_pcie_dw *pcie)
{
pcie->slot_ctl_3v3 = devm_regulator_get_optional(pcie->dev, "vpcie3v3");
if (IS_ERR(pcie->slot_ctl_3v3)) {
if (PTR_ERR(pcie->slot_ctl_3v3) != -ENODEV)
return PTR_ERR(pcie->slot_ctl_3v3);
pcie->slot_ctl_3v3 = NULL;
}
pcie->slot_ctl_12v = devm_regulator_get_optional(pcie->dev, "vpcie12v");
if (IS_ERR(pcie->slot_ctl_12v)) {
if (PTR_ERR(pcie->slot_ctl_12v) != -ENODEV)
return PTR_ERR(pcie->slot_ctl_12v);
pcie->slot_ctl_12v = NULL;
}
return 0;
}
static int tegra_pcie_enable_slot_regulators(struct tegra_pcie_dw *pcie)
{
int ret;
if (pcie->slot_ctl_3v3) {
ret = regulator_enable(pcie->slot_ctl_3v3);
if (ret < 0) {
dev_err(pcie->dev,
"Failed to enable 3.3V slot supply: %d\n", ret);
return ret;
}
}
if (pcie->slot_ctl_12v) {
ret = regulator_enable(pcie->slot_ctl_12v);
if (ret < 0) {
dev_err(pcie->dev,
"Failed to enable 12V slot supply: %d\n", ret);
goto fail_12v_enable;
}
}
/*
* According to PCI Express Card Electromechanical Specification
* Revision 1.1, Table-2.4, T_PVPERL (Power stable to PERST# inactive)
* should be a minimum of 100ms.
*/
if (pcie->slot_ctl_3v3 || pcie->slot_ctl_12v)
msleep(100);
return 0;
fail_12v_enable:
if (pcie->slot_ctl_3v3)
regulator_disable(pcie->slot_ctl_3v3);
return ret;
}
static void tegra_pcie_disable_slot_regulators(struct tegra_pcie_dw *pcie)
{
if (pcie->slot_ctl_12v)
regulator_disable(pcie->slot_ctl_12v);
if (pcie->slot_ctl_3v3)
regulator_disable(pcie->slot_ctl_3v3);
}
static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
bool en_hw_hot_rst)
{
@ -1068,6 +1137,10 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
return ret;
}
ret = tegra_pcie_enable_slot_regulators(pcie);
if (ret < 0)
goto fail_slot_reg_en;
ret = regulator_enable(pcie->pex_ctl_supply);
if (ret < 0) {
dev_err(pcie->dev, "Failed to enable regulator: %d\n", ret);
@ -1150,6 +1223,8 @@ fail_core_apb_rst:
fail_core_clk:
regulator_disable(pcie->pex_ctl_supply);
fail_reg_en:
tegra_pcie_disable_slot_regulators(pcie);
fail_slot_reg_en:
tegra_pcie_bpmp_set_ctrl_state(pcie, false);
return ret;
@ -1182,6 +1257,8 @@ static int __deinit_controller(struct tegra_pcie_dw *pcie)
return ret;
}
tegra_pcie_disable_slot_regulators(pcie);
ret = tegra_pcie_bpmp_set_ctrl_state(pcie, false);
if (ret) {
dev_err(pcie->dev, "Failed to disable controller %d: %d\n",
@ -1381,6 +1458,12 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
return ret;
}
ret = tegra_pcie_get_slot_regulators(pcie);
if (ret < 0) {
dev_err(dev, "Failed to get slot regulators: %d\n", ret);
return ret;
}
pcie->pex_ctl_supply = devm_regulator_get(dev, "vddio-pex-ctl");
if (IS_ERR(pcie->pex_ctl_supply)) {
ret = PTR_ERR(pcie->pex_ctl_supply);