diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-designware-host.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware-host.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 9952057c8819..a7170fd0e847 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -8,6 +8,7 @@ * Author: Jingoo Han <jg1.han@samsung.com> */ +#include <linux/iopoll.h> #include <linux/irqchip/chained_irq.h> #include <linux/irqdomain.h> #include <linux/msi.h> @@ -16,6 +17,7 @@ #include <linux/pci_regs.h> #include <linux/platform_device.h> +#include "../../pci.h" #include "pcie-designware.h" static struct pci_ops dw_pcie_ops; @@ -807,3 +809,72 @@ int dw_pcie_setup_rc(struct dw_pcie_rp *pp) return 0; } EXPORT_SYMBOL_GPL(dw_pcie_setup_rc); + +int dw_pcie_suspend_noirq(struct dw_pcie *pci) +{ + u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); + u32 val; + int ret; + + /* + * If L1SS is supported, then do not put the link into L2 as some + * devices such as NVMe expect low resume latency. + */ + if (dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKCTL) & PCI_EXP_LNKCTL_ASPM_L1) + return 0; + + if (dw_pcie_get_ltssm(pci) <= DW_PCIE_LTSSM_DETECT_ACT) + return 0; + + if (!pci->pp.ops->pme_turn_off) + return 0; + + pci->pp.ops->pme_turn_off(&pci->pp); + + ret = read_poll_timeout(dw_pcie_get_ltssm, val, val == DW_PCIE_LTSSM_L2_IDLE, + PCIE_PME_TO_L2_TIMEOUT_US/10, + PCIE_PME_TO_L2_TIMEOUT_US, false, pci); + if (ret) { + dev_err(pci->dev, "Timeout waiting for L2 entry! LTSSM: 0x%x\n", val); + return ret; + } + + if (pci->pp.ops->host_deinit) + pci->pp.ops->host_deinit(&pci->pp); + + pci->suspended = true; + + return ret; +} +EXPORT_SYMBOL_GPL(dw_pcie_suspend_noirq); + +int dw_pcie_resume_noirq(struct dw_pcie *pci) +{ + int ret; + + if (!pci->suspended) + return 0; + + pci->suspended = false; + + if (pci->pp.ops->host_init) { + ret = pci->pp.ops->host_init(&pci->pp); + if (ret) { + dev_err(pci->dev, "Host init failed: %d\n", ret); + return ret; + } + } + + dw_pcie_setup_rc(&pci->pp); + + ret = dw_pcie_start_link(pci); + if (ret) + return ret; + + ret = dw_pcie_wait_for_link(pci); + if (ret) + return ret; + + return ret; +} +EXPORT_SYMBOL_GPL(dw_pcie_resume_noirq); |