[PATCH 06/21] scsi: ufs: Add support to manage multiple power domains in ufshcd-pltfrm

Rajendra Nayak
2020-04-08T13:47:39Z

Some UFS devices need to manage multiple powerdomains. Add support for
it as part of the ufshcd-pltfrm driver.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Can Guo <cang@codeaurora.org>
Cc: Asutosh Das <asutoshd@codeaurora.org>
Cc: Subhash Jadavani <subhashj@codeaurora.org>
Cc: linux-scsi@vger.kernel.org
---
drivers/scsi/ufs/ufshcd-pltfrm.c | 58 ++++++++++++++++++++++++++++++++++++++--
drivers/scsi/ufs/ufshcd.h | 3 +++
2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 76f9be7..d40b4a7 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -34,8 +34,10 @@
*/

#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
+#include <linux/pm_opp.h>

#include "ufshcd.h"
#include "ufshcd-pltfrm.h"
@@ -282,6 +284,44 @@ static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
}
}

+static int ufshcd_attach_pds(struct device *dev, struct ufs_hba *hba, int num_pds)
+{
+ struct opp_table *opp;
+ struct device **opp_virt_dev;
+ const char *opp_pds[] = { "rpmh_pd", NULL };
+
+ if (num_pds > 2)
+ return -EINVAL;
+
+ /* Attach the power domain for on/off control */
+ hba->gdsc_virt_dev = dev_pm_domain_attach_by_name(dev, "gdsc_pd");
+ if (IS_ERR(hba->gdsc_virt_dev))
+ return PTR_ERR(hba->gdsc_virt_dev);
+
+ device_link_add(dev, hba->gdsc_virt_dev, DL_FLAG_RPM_ACTIVE |
+ DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS);
+
+
+ /* Attach the power domain for setting performance state */
+ opp = dev_pm_opp_attach_genpd(dev, opp_pds, &opp_virt_dev);
+ if (IS_ERR(opp))
+ return PTR_ERR(opp);
+ else if (opp_virt_dev) {
+ hba->opp_virt_dev = *opp_virt_dev;
+
+ device_link_add(dev, hba->opp_virt_dev, DL_FLAG_RPM_ACTIVE |
+ DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS);
+ }
+
+ return 0;
+}
+
+static void ufshcd_detach_pds(struct ufs_hba *hba)
+{
+ dev_pm_domain_detach(hba->gdsc_virt_dev, false);
+ dev_pm_domain_detach(hba->opp_virt_dev, false);
+}
+
/**
* ufshcd_get_pwr_dev_param - get finally agreed attributes for
* power mode change
@@ -391,7 +431,7 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
{
struct ufs_hba *hba;
void __iomem *mmio_base;
- int irq, err;
+ int irq, err, num_pds;
struct device *dev = &pdev->dev;

mmio_base = devm_platform_ioremap_resource(pdev, 0);
@@ -429,10 +469,21 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,

ufshcd_init_lanes_per_dir(hba);

+ num_pds = of_count_phandle_with_args(dev->of_node, "power-domains",
+ "#power-domain-cells");
+ if (num_pds > 1) {
+ err = ufshcd_attach_pds(&pdev->dev, hba, num_pds);
+ if (err) {
+ dev_err(&pdev->dev, "%s: attach of power domains failed %d\n",
+ __func__, err);
+ goto dealloc_host;
+ }
+ }
+
err = ufshcd_init(hba, mmio_base, irq);
if (err) {
dev_err(dev, "Initialization failed\n");
- goto dealloc_host;
+ goto detach_pds;
}

platform_set_drvdata(pdev, hba);
@@ -442,6 +493,9 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,

return 0;

+detach_pds:
+ if (num_pds > 1)
+ ufshcd_detach_pds(hba);
dealloc_host:
ufshcd_dealloc_host(hba);
out:
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index dd1ee27..ed3fbad 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -612,6 +612,9 @@ struct ufs_hba {
struct Scsi_Host *host;
struct device *dev;
struct request_queue *cmd_queue;
+ struct device *gdsc_virt_dev;
+ struct device *opp_virt_dev;
+
/*
* This field is to keep a reference to "scsi_device" corresponding to
* "UFS device" W-LU.