net: hns: Add support of ACPI to HNS driver RoCE Reset function

In the Hip06 SoC, the RoCE Engine is part of the Hisilicon Network
Subsystem and is dependent upon DSAF module. Therefore, certain
functions like RESET are exposed through the common registers of
HNS DSAF module which are memory-mapped by the HNS driver and
currently can only be accessed through DT/syscon interface.

This patch adds the support of ACPI to the existing RoCE reset
function in the HNS driver(please refer NOTE 2). Hisilicon RoCE
driver (please refer NOTE 1) shall call this reset function during
probe time to reset the RoCE Engine.

The HNS Reset function indirectly ends up in calling the _DSM()
function part of the DSDT ACPI Table. Actual reset functionality
for ACPI is implemented within the ACPI DSDT Table which also has
been enhanced to support this change.

Support of ACPI in the HNS RoCE driver shall be pushed through a
different accompanying below patch:
"IB/hns: Add support of ACPI to the Hisilicon RoCE Driver"

NOTE 1: HNS RoCE driver has already been accepted by its maintainer
Doug Ledford<dledford@redhat.com>. Please refer below link:
https://www.spinics.net/lists/linux-rdma/msg38850.html

NOTE 2: RoCE reset function patch has been accepted and now is
part of the net-next:
https://www.mail-archive.com/netdev@vger.kernel.org/msg123867.html

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Reviewed-by: Yisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 49 insertions, 4 deletions

diff --git a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_misc.c b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_misc.c
index 36b9f791cf2f..67accce1d33d 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_misc.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_misc.c
@@ -26,6 +26,8 @@ enum _dsm_rst_type {
 	HNS_XGE_CORE_RESET_FUNC = 0x3,
 	HNS_XGE_RESET_FUNC      = 0x4,
 	HNS_GE_RESET_FUNC       = 0x5,
+	HNS_DSAF_CHN_RESET_FUNC = 0x6,
+	HNS_ROCE_RESET_FUNC     = 0x7,
 };
 
 const u8 hns_dsaf_acpi_dsm_uuid[] = {
@@ -241,11 +243,11 @@ static void hns_dsaf_xge_core_srst_by_port(struct dsaf_device *dsaf_dev,
  * bit18-19 for com/dfx
  * @enable: false - request reset , true - drop reset
  */
-void hns_dsaf_srst_chns(struct dsaf_device *dsaf_dev, u32 msk, bool enable)
+void hns_dsaf_srst_chns(struct dsaf_device *dsaf_dev, u32 msk, bool dereset)
 {
 	u32 reg_addr;
 
-	if (!enable)
+	if (!dereset)
 		reg_addr = DSAF_SUB_SC_DSAF_RESET_REQ_REG;
 	else
 		reg_addr = DSAF_SUB_SC_DSAF_RESET_DREQ_REG;
@@ -253,9 +255,27 @@ void hns_dsaf_srst_chns(struct dsaf_device *dsaf_dev, u32 msk, bool enable)
 	dsaf_write_sub(dsaf_dev, reg_addr, msk);
 }
 
-void hns_dsaf_roce_srst(struct dsaf_device *dsaf_dev, bool enable)
+/**
+ * hns_dsaf_srst_chns - reset dsaf channels
+ * @dsaf_dev: dsaf device struct pointer
+ * @msk: xbar channels mask value:
+ * bit0-5 for xge0-5
+ * bit6-11 for ppe0-5
+ * bit12-17 for roce0-5
+ * bit18-19 for com/dfx
+ * @enable: false - request reset , true - drop reset
+ */
+void
+hns_dsaf_srst_chns_acpi(struct dsaf_device *dsaf_dev, u32 msk, bool dereset)
 {
-	if (!enable) {
+	hns_dsaf_acpi_srst_by_port(dsaf_dev, HNS_OP_RESET_FUNC,
+				   HNS_DSAF_CHN_RESET_FUNC,
+				   msk, dereset);
+}
+
+void hns_dsaf_roce_srst(struct dsaf_device *dsaf_dev, bool dereset)
+{
+	if (!dereset) {
 		dsaf_write_sub(dsaf_dev, DSAF_SUB_SC_ROCEE_RESET_REQ_REG, 1);
 	} else {
 		dsaf_write_sub(dsaf_dev,
@@ -267,6 +287,12 @@ void hns_dsaf_roce_srst(struct dsaf_device *dsaf_dev, bool enable)
 	}
 }
 
+void hns_dsaf_roce_srst_acpi(struct dsaf_device *dsaf_dev, bool dereset)
+{
+	hns_dsaf_acpi_srst_by_port(dsaf_dev, HNS_OP_RESET_FUNC,
+				   HNS_ROCE_RESET_FUNC, 0, dereset);
+}
+
 static void
 hns_dsaf_xge_core_srst_by_port_acpi(struct dsaf_device *dsaf_dev,
 				    u32 port, bool dereset)
@@ -575,6 +601,8 @@ struct dsaf_misc_op *hns_misc_op_get(struct dsaf_device *dsaf_dev)
 		misc_op->ge_srst = hns_dsaf_ge_srst_by_port;
 		misc_op->ppe_srst = hns_ppe_srst_by_port;
 		misc_op->ppe_comm_srst = hns_ppe_com_srst;
+		misc_op->hns_dsaf_srst_chns = hns_dsaf_srst_chns;
+		misc_op->hns_dsaf_roce_srst = hns_dsaf_roce_srst;
 
 		misc_op->get_phy_if = hns_mac_get_phy_if;
 		misc_op->get_sfp_prsnt = hns_mac_get_sfp_prsnt;
@@ -591,6 +619,8 @@ struct dsaf_misc_op *hns_misc_op_get(struct dsaf_device *dsaf_dev)
 		misc_op->ge_srst = hns_dsaf_ge_srst_by_port_acpi;
 		misc_op->ppe_srst = hns_ppe_srst_by_port_acpi;
 		misc_op->ppe_comm_srst = hns_ppe_com_srst;
+		misc_op->hns_dsaf_srst_chns = hns_dsaf_srst_chns_acpi;
+		misc_op->hns_dsaf_roce_srst = hns_dsaf_roce_srst_acpi;
 
 		misc_op->get_phy_if = hns_mac_get_phy_if_acpi;
 		misc_op->get_sfp_prsnt = hns_mac_get_sfp_prsnt;
@@ -603,3 +633,18 @@ struct dsaf_misc_op *hns_misc_op_get(struct dsaf_device *dsaf_dev)
 
 	return (void *)misc_op;
 }
+
+static int hns_dsaf_dev_match(struct device *dev, void *fwnode)
+{
+	return dev->fwnode == fwnode;
+}
+
+struct
+platform_device *hns_dsaf_find_platform_device(struct fwnode_handle *fwnode)
+{
+	struct device *dev;
+
+	dev = bus_find_device(&platform_bus_type, NULL,
+			      fwnode, hns_dsaf_dev_match);
+	return dev ? to_platform_device(dev) : NULL;
+}