On 7/7/2023 11:34 AM, Manivannan Sadhasivam wrote:
On Fri, Jun 30, 2023 at 04:22:07PM +0530, Krishna chaitanya chundru wrote:
Endpoint cannot send any data/MSI when the D-state is in
D3cold or D3hot. Endpoint needs to bring the host back to D0
Endpoint needs to wake up the host to bring the D-state to D0
to send any kind of data.
Endpoint can toggle wake signal when the D-state is in D3cold and vaux is
not supplied or can send inband PME.
To support this adding wake up host to epc core.
"add wakeup_host() callback to the EPC core".
Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
---
Documentation/PCI/endpoint/pci-endpoint.rst | 6 ++++++
drivers/pci/endpoint/pci-epc-core.c | 31 +++++++++++++++++++++++++++++
include/linux/pci-epc.h | 11 ++++++++++
3 files changed, 48 insertions(+)
diff --git a/Documentation/PCI/endpoint/pci-endpoint.rst b/Documentation/PCI/endpoint/pci-endpoint.rst
index 0538cdc..186ce3b 100644
--- a/Documentation/PCI/endpoint/pci-endpoint.rst
+++ b/Documentation/PCI/endpoint/pci-endpoint.rst
@@ -53,6 +53,7 @@ by the PCI controller driver.
* raise_irq: ops to raise a legacy, MSI or MSI-X interrupt
* start: ops to start the PCI link
* stop: ops to stop the PCI link
+ * wakeup_host: ops to wake host
wakeup
The PCI controller driver can then create a new EPC device by invoking
devm_pci_epc_create()/pci_epc_create().
@@ -122,6 +123,11 @@ by the PCI endpoint function driver.
The PCI endpoint function driver should use pci_epc_mem_free_addr() to
free the memory space allocated using pci_epc_mem_alloc_addr().
+* pci_epc_wakeup_host()
+
+ The PCI endpoint function driver should use pci_epc_wakeup_host() to wake
wakeup
+ host.
+
Other EPC APIs
~~~~~~~~~~~~~~
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index cad360f..23599b8 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -167,6 +167,37 @@ const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc,
EXPORT_SYMBOL_GPL(pci_epc_get_features);
/**
+ * pci_epc_wakeup_host() - Wakeup the host
+ * @epc: the EPC device which has to wake the host
wakeup
+ * @func_no: the physical endpoint function number in the EPC device
+ * @vfunc_no: the virtual endpoint function number in the physical function
+ * @type: specify the type of wakeup: WAKEUP_FROM_D3COLD, WAKEUP_FROM_D3HOT
+ *
+ * Invoke to wakeup host
+ */
+int pci_epc_wakeup_host(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
+ enum pci_epc_wakeup_host_type type)
Why can't you use a bool?
- Mani
Sure I will change it to bool as suggested.
- KC
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
+ return -EINVAL;
+
+ if (vfunc_no > 0 && (!epc->max_vfs || vfunc_no > epc->max_vfs[func_no]))
+ return -EINVAL;
+
+ if (!epc->ops->wakeup_host)
+ return 0;
+
+ mutex_lock(&epc->lock);
+ ret = epc->ops->wakeup_host(epc, func_no, vfunc_no, type);
+ mutex_unlock(&epc->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pci_epc_wakeup_host);
+
+/**
* pci_epc_stop() - stop the PCI link
* @epc: the link of the EPC device that has to be stopped
*
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index 26a1108..2323a10 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -26,6 +26,12 @@ enum pci_epc_irq_type {
PCI_EPC_IRQ_MSIX,
};
+enum pci_epc_wakeup_host_type {
+ PCI_WAKEUP_UNKNOWN,
+ PCI_WAKEUP_SEND_PME,
+ PCI_WAKEUP_TOGGLE_WAKE,
+};
+
static inline const char *
pci_epc_interface_string(enum pci_epc_interface_type type)
{
@@ -59,6 +65,7 @@ pci_epc_interface_string(enum pci_epc_interface_type type)
* @start: ops to start the PCI link
* @stop: ops to stop the PCI link
* @get_features: ops to get the features supported by the EPC
+ * @wakeup_host: ops to wakeup the host
* @owner: the module owner containing the ops
*/
struct pci_epc_ops {
@@ -88,6 +95,8 @@ struct pci_epc_ops {
void (*stop)(struct pci_epc *epc);
const struct pci_epc_features* (*get_features)(struct pci_epc *epc,
u8 func_no, u8 vfunc_no);
+ int (*wakeup_host)(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
+ enum pci_epc_wakeup_host_type type);
struct module *owner;
};
@@ -234,6 +243,8 @@ int pci_epc_start(struct pci_epc *epc);
void pci_epc_stop(struct pci_epc *epc);
const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc,
u8 func_no, u8 vfunc_no);
+int pci_epc_wakeup_host(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
+ enum pci_epc_wakeup_host_type type);
enum pci_barno
pci_epc_get_first_free_bar(const struct pci_epc_features *epc_features);
enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features
--
2.7.4
