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path: root/drivers/pci/controller/dwc/pcie-designware-host.c
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Diffstat (limited to 'drivers/pci/controller/dwc/pcie-designware-host.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-designware-host.c71
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);