[PATCH v5 11/14] PCI: rockship-ep: Implement the pci_epc_ops::stop_link() operation

Damien Le Moal
2024-10-17T01:59:14Z

Define the EPC operation ->stop() for the Rockchip endpoint driver with
the function rockchip_pcie_ep_stop(). This function disables link
training and the controller configuration, as the reverse to what
the start operation defined with rockchip_pcie_ep_start() does.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
drivers/pci/controller/pcie-rockchip-ep.c | 13 +++++++++++++
drivers/pci/controller/pcie-rockchip.h | 1 +
2 files changed, 14 insertions(+)

diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index 256a90485fe4..2f7709ba1cac 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -473,6 +473,18 @@ static int rockchip_pcie_ep_start(struct pci_epc *epc)
return 0;
}

+static void rockchip_pcie_ep_stop(struct pci_epc *epc)
+{
+ struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
+ struct rockchip_pcie *rockchip = &ep->rockchip;
+
+ /* Stop link training and disable configuration */
+ rockchip_pcie_write(rockchip,
+ PCIE_CLIENT_CONF_DISABLE |
+ PCIE_CLIENT_LINK_TRAIN_DISABLE,
+ PCIE_CLIENT_CONFIG);
+}
+
static const struct pci_epc_features rockchip_pcie_epc_features = {
.linkup_notifier = false,
.msi_capable = true,
@@ -497,6 +509,7 @@ static const struct pci_epc_ops rockchip_pcie_epc_ops = {
.get_msi = rockchip_pcie_ep_get_msi,
.raise_irq = rockchip_pcie_ep_raise_irq,
.start = rockchip_pcie_ep_start,
+ .stop = rockchip_pcie_ep_stop,
.get_features = rockchip_pcie_ep_get_features,
};

diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index 30398156095f..0263f158ee8d 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -32,6 +32,7 @@
#define PCIE_CLIENT_CONF_ENABLE HIWORD_UPDATE_BIT(0x0001)
#define PCIE_CLIENT_CONF_DISABLE HIWORD_UPDATE(0x0001, 0)
#define PCIE_CLIENT_LINK_TRAIN_ENABLE HIWORD_UPDATE_BIT(0x0002)
+#define PCIE_CLIENT_LINK_TRAIN_DISABLE HIWORD_UPDATE(0x0002, 0)
#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)
--
2.47.0