On 8/22/2023 9:33 AM, Pavan Kondeti wrote:
On Mon, Aug 21, 2023 at 07:45:43PM +0530, Krishna chaitanya chundru wrote:
Before link training vote for the maximum performance state of RPMH
and once link is up, vote for the performance state based upon the link
speed.
Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-qcom.c | 47 ++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 7a87a47..c57ca1a 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -22,6 +22,7 @@
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/pci.h>
+#include <linux/pm_opp.h>
#include <linux/pm_runtime.h>
#include <linux/platform_device.h>
#include <linux/phy/pcie.h>
@@ -1357,6 +1358,32 @@ static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
return 0;
}
+static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
+{
+ struct dw_pcie *pci = pcie->pci;
+ struct dev_pm_opp *opp;
+ u32 offset, status;
+ int speed, ret = 0;
+
+ offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+ status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
+
+ /* Only update constraints if link is up. */
+ if (!(status & PCI_EXP_LNKSTA_DLLLA))
+ return;
+
What happens if link is not up during probe? We set max vote before
this, should not we bring it down in suspend and vote it back again in
resume?
ok, I will set to lower value in the suspend path if the link is not
up. If the link is already up driver will not
do any modifications.
+ speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
+
+ opp = dev_pm_opp_find_level_exact(pci->dev, speed);
+ if (!IS_ERR(opp)) {
+ ret = dev_pm_opp_set_opp(pci->dev, opp);
+ if (ret)
+ dev_err(pci->dev, "Failed to set opp: %d\n", ret);
+ dev_pm_opp_put(opp);
+ }
Since you added an error message, make it more useful by printing the
opp level also. dev_pm_opp_get_level().
Sure I will add this in next patch.
+
+}
+
static void qcom_pcie_icc_update(struct qcom_pcie *pcie)
{
struct dw_pcie *pci = pcie->pci;
@@ -1439,8 +1466,10 @@ static void qcom_pcie_init_debugfs(struct qcom_pcie *pcie)
static int qcom_pcie_probe(struct platform_device *pdev)
{
const struct qcom_pcie_cfg *pcie_cfg;
+ unsigned long max_freq = INT_MAX;
struct device *dev = &pdev->dev;
struct qcom_pcie *pcie;
+ struct dev_pm_opp *opp;
struct dw_pcie_rp *pp;
struct resource *res;
struct dw_pcie *pci;
@@ -1511,6 +1540,22 @@ static int qcom_pcie_probe(struct platform_device *pdev)
if (ret)
goto err_pm_runtime_put;
+ /* OPP table is optional */
+ ret = devm_pm_opp_of_add_table(dev);
+ if (ret && ret != -ENODEV) {
+ dev_err(dev, "Invalid OPP table in Device tree\n");
+ goto err_pm_runtime_put;
+ }
+
+ /* vote for max level in the opp table */
+ opp = dev_pm_opp_find_freq_floor(dev, &max_freq);
+ if (!IS_ERR(opp)) {
+ ret = dev_pm_opp_set_opp(dev, opp);
+ if (ret)
+ dev_err(pci->dev, "Failed to set opp: %d\n", ret);
+ dev_pm_opp_put(opp);
+ }
+
This needs an update since you moved from frequency based voting to link
speed based voting.
dev_pm_opp_find_freq_floor will give us the max the opp level opp we
don't have a similar API to get max opp-level
For that reason we are using this API.
- KC
ret = pcie->cfg->ops->get_resources(pcie);
if (ret)
goto err_pm_runtime_put;
@@ -1531,6 +1576,8 @@ static int qcom_pcie_probe(struct platform_device *pdev)
qcom_pcie_icc_update(pcie);
+ qcom_pcie_opp_update(pcie);
+
if (pcie->mhi)
qcom_pcie_init_debugfs(pcie);
Thanks,
Pavan
