clk: zynqmp: Warn user if clock user are more than allowed

Warn user if clock is used by more than allowed devices.
This check is done by firmware and returns respective
error code. Upon receiving error code for excessive user,
warn user for the same.

This change is done to restrict VPLL use count. It is
assumed that VPLL is used by one user only.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Link: https://lkml.kernel.org/r/1575527759-26452-4-git-send-email-rajan.vaja@xilinx.com
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

diff --git a/drivers/clk/zynqmp/pll.c b/drivers/clk/zynqmp/pll.c
index a541397a172c86705d9cc0886e4206f91019872f..89b59953010515d30698e835590175260658d3d6 100644 (file)
--- a/drivers/clk/zynqmp/pll.c
+++ b/drivers/clk/zynqmp/pll.c
@@ -188,10 +188,12 @@ static int zynqmp_pll_set_rate(struct clk_hw *hw, unsigned long rate,
                frac = (parent_rate * f) / FRAC_DIV;
 
                ret = eemi_ops->clock_setdivider(clk_id, m);
-               if (ret)
+               if (ret == -EUSERS)
+                       WARN(1, "More than allowed devices are using the %s, which is forbidden\n",
+                            clk_name);
+               else if (ret)
                        pr_warn_once("%s() set divider failed for %s, ret = %d\n",
                                     __func__, clk_name, ret);
-
                eemi_ops->ioctl(0, IOCTL_SET_PLL_FRAC_DATA, clk_id, f, NULL);
 
                return rate + frac;

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 75bdfaa08380018bad1321b0a7ec91b4741bb20c..74d9f13d72c45f4c1c9052d044b70d0c341ba53a 100644 (file)
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -48,6 +48,8 @@ static int zynqmp_pm_ret_code(u32 ret_status)
                return -EACCES;
        case XST_PM_ABORT_SUSPEND:
                return -ECANCELED;
+       case XST_PM_MULT_USER:
+               return -EUSERS;
        case XST_PM_INTERNAL:
        case XST_PM_CONFLICT:
        case XST_PM_INVALID_NODE:

diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
index e41ad9e3713606507e4e3c0e6d4378adcc2a69b0..1827d30e86f16447a85f4d06f67040609e4cc9c3 100644 (file)
--- a/include/linux/firmware/xlnx-zynqmp.h
+++ b/include/linux/firmware/xlnx-zynqmp.h
@@ -89,6 +89,7 @@ enum pm_ret_status {
        XST_PM_INVALID_NODE,
        XST_PM_DOUBLE_REQ,
        XST_PM_ABORT_SUSPEND,
+       XST_PM_MULT_USER = 2008,
 };
 
 enum pm_ioctl_id {