From:   Mikko Perttunen <cyndis@kapsi.fi>
To:     Lorenzo Pieralisi <lpieralisi@kernel.org>,
        =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= <kw@linux.com>,
        Rob Herring <robh@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>
Cc:     Mikko Perttunen <mperttunen@nvidia.com>, linux-pci@vger.kernel.org,
        linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2] PCI: tegra194: Handle errors in BPMP response
Date:   Wed,  8 Feb 2023 16:27:35 +0200
Message-Id: <20230208142735.3218707-1-cyndis@kapsi.fi>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Mikko Perttunen <mperttunen@nvidia.com>

The return value from tegra_bpmp_transfer indicates the success or
failure of the IPC transaction with BPMP. If the transaction
succeeded, we also need to check the actual command's result code.
Add code to do this.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/pci/controller/dwc/pcie-tegra194.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 02d78a12b6e7..cf5fd1c2efd3 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1200,6 +1200,7 @@ static int tegra_pcie_bpmp_set_ctrl_state(struct tegra_pcie_dw *pcie,
 	struct mrq_uphy_response resp;
 	struct tegra_bpmp_message msg;
 	struct mrq_uphy_request req;
+	int err;
 
 	/*
 	 * Controller-5 doesn't need to have its state set by BPMP-FW in
@@ -1222,7 +1223,13 @@ static int tegra_pcie_bpmp_set_ctrl_state(struct tegra_pcie_dw *pcie,
 	msg.rx.data = &resp;
 	msg.rx.size = sizeof(resp);
 
-	return tegra_bpmp_transfer(pcie->bpmp, &msg);
+	err = tegra_bpmp_transfer(pcie->bpmp, &msg);
+	if (err)
+		return err;
+	if (msg.rx.ret)
+		return -EINVAL;
+
+	return 0;
 }
 
 static int tegra_pcie_bpmp_set_pll_state(struct tegra_pcie_dw *pcie,
@@ -1231,6 +1238,7 @@ static int tegra_pcie_bpmp_set_pll_state(struct tegra_pcie_dw *pcie,
 	struct mrq_uphy_response resp;
 	struct tegra_bpmp_message msg;
 	struct mrq_uphy_request req;
+	int err;
 
 	memset(&req, 0, sizeof(req));
 	memset(&resp, 0, sizeof(resp));
@@ -1250,7 +1258,13 @@ static int tegra_pcie_bpmp_set_pll_state(struct tegra_pcie_dw *pcie,
 	msg.rx.data = &resp;
 	msg.rx.size = sizeof(resp);
 
-	return tegra_bpmp_transfer(pcie->bpmp, &msg);
+	err = tegra_bpmp_transfer(pcie->bpmp, &msg);
+	if (err)
+		return err;
+	if (msg.rx.ret)
+		return -EINVAL;
+
+	return 0;
 }
 
 static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
-- 
2.39.0