NTB: add helper functions to set and clear sideinfo

We define two new helper functions to set and clear
sideinfo registers respectively. These functions
take an additional boolean parameter which signifies
whether we want to set/clear the sideinfo register
of the peer(true) or local host(false).
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

drivers/ntb/hw/amd/ntb_hw_amd.c

@@ -913,28 +913,32 @@ static int amd_init_isr(struct amd_ntb_dev *ndev)
 	return ndev_init_isr(ndev, AMD_DB_CNT, AMD_MSIX_VECTOR_CNT);
 }
 
-static void amd_init_side_info(struct amd_ntb_dev *ndev)
+static void amd_set_side_info_reg(struct amd_ntb_dev *ndev, bool peer)
 {
-	void __iomem *mmio = ndev->self_mmio;
+	void __iomem *mmio = NULL;
 	unsigned int reg;
-	u32 ntb_ctl;
+
+	if (peer)
+		mmio = ndev->peer_mmio;
+	else
+		mmio = ndev->self_mmio;
 
 	reg = readl(mmio + AMD_SIDEINFO_OFFSET);
 	if (!(reg & AMD_SIDE_READY)) {
 		reg |= AMD_SIDE_READY;
 		writel(reg, mmio + AMD_SIDEINFO_OFFSET);
 	}
-
-	ntb_ctl = readl(mmio + AMD_CNTL_OFFSET);
-	ntb_ctl |= (PMM_REG_CTL | SMM_REG_CTL);
-	writel(ntb_ctl, mmio + AMD_CNTL_OFFSET);
 }
 
-static void amd_deinit_side_info(struct amd_ntb_dev *ndev)
+static void amd_clear_side_info_reg(struct amd_ntb_dev *ndev, bool peer)
 {
-	void __iomem *mmio = ndev->self_mmio;
+	void __iomem *mmio = NULL;
 	unsigned int reg;
-	u32 ntb_ctl;
+
+	if (peer)
+		mmio = ndev->peer_mmio;
+	else
+		mmio = ndev->self_mmio;
 
 	reg = readl(mmio + AMD_SIDEINFO_OFFSET);
 	if (reg & AMD_SIDE_READY) {
@@ -942,6 +946,26 @@ static void amd_deinit_side_info(struct amd_ntb_dev *ndev)
 		writel(reg, mmio + AMD_SIDEINFO_OFFSET);
 		readl(mmio + AMD_SIDEINFO_OFFSET);
 	}
+}
+
+static void amd_init_side_info(struct amd_ntb_dev *ndev)
+{
+	void __iomem *mmio = ndev->self_mmio;
+	u32 ntb_ctl;
+
+	amd_set_side_info_reg(ndev, false);
+
+	ntb_ctl = readl(mmio + AMD_CNTL_OFFSET);
+	ntb_ctl |= (PMM_REG_CTL | SMM_REG_CTL);
+	writel(ntb_ctl, mmio + AMD_CNTL_OFFSET);
+}
+
+static void amd_deinit_side_info(struct amd_ntb_dev *ndev)
+{
+	void __iomem *mmio = ndev->self_mmio;
+	u32 ntb_ctl;
+
+	amd_clear_side_info_reg(ndev, false);
 
 	ntb_ctl = readl(mmio + AMD_CNTL_OFFSET);
 	ntb_ctl &= ~(PMM_REG_CTL | SMM_REG_CTL);

drivers/ntb/hw/amd/ntb_hw_amd.h

@@ -215,4 +215,7 @@ struct amd_ntb_dev {
 #define ntb_ndev(__ntb) container_of(__ntb, struct amd_ntb_dev, ntb)
 #define hb_ndev(__work) container_of(__work, struct amd_ntb_dev, hb_timer.work)
 
+static void amd_set_side_info_reg(struct amd_ntb_dev *ndev, bool peer);
+static void amd_clear_side_info_reg(struct amd_ntb_dev *ndev, bool peer);
+
 #endif