video: tegra: host: pva: Add frequency scaling

This change adds frequency scaling support to PVA. The change allows
differnt PVA users to request minimum frequency or bandiwdth requirement.
This frequency is then propagated to all PVA clocks (R5, VPS0 and VPS1).

nvhost implements clock scaling by:
* Going through all bandwidth requests and summing them up
* Going through all minimum requests and taking maximum over them
* Taking maximum of summed bandiwdth requests and minimum frequency
  requests.

JIRA PVA-101

Change-Id: Ib895ffd7eafe3379b097ade740750a2d99464b73
Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1628404
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Vinod Gopalakrishnakurup <vinodg@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 33 insertions, 2 deletions

diff --git a/include/uapi/linux/nvhost_pva_ioctl.h b/include/uapi/linux/nvhost_pva_ioctl.h
index 233b9eca5..520c47b9c 100644
--- a/include/uapi/linux/nvhost_pva_ioctl.h
+++ b/include/uapi/linux/nvhost_pva_ioctl.h
@@ -1,7 +1,7 @@
 /*
  * Tegra PVA Driver ioctls
  *
- * Copyright (c) 2016-2017, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2016-2018, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -295,6 +295,33 @@ struct pva_ioctl_vpu_func_table {
         __u32 size;
 };
 
+/**
+ * enum pva_clk_type - Clock type identifier while setting the frequency.
+ *
+ * PVA KMD supports three request types: Minimum, bandwidth and bandwidth
+ * (kHz). All bandwidth requests are summed up and treated as one of the
+ * minimum frequency requests. KMD then takes the maximum over all minimum
+ * requests and tries to set the frequency to PVA.
+ */
+enum pva_clk_type {
+        PVA_CLOCK       = 0,
+        PVA_BW          = 1,
+        PVA_BW_KHZ      = 3,
+};
+
+/**
+ * struct pva_ioctl_rate - Requesting PVA frequency update
+ *
+ * @param rate: Requested rate
+ * @param type: Type of the request according to pva_clk_type
+ * @param reserved: Reserved for future usage. Must be 0.
+ */
+struct pva_ioctl_rate {
+        __u64 rate;
+        __u32 type;
+        __u32 reserved;
+};
+
 #define PVA_IOCTL_CHARACTERISTICS       \
         _IOWR(NVHOST_PVA_IOCTL_MAGIC, 1, struct pva_characteristics_req)
 #define PVA_IOCTL_PIN   \
@@ -307,9 +334,13 @@ struct pva_ioctl_vpu_func_table {
         _IOW(NVHOST_PVA_IOCTL_MAGIC, 5, struct pva_ioctl_queue_attr)
 #define PVA_IOCTL_COPY_VPU_FUNCTION_TABLE       \
         _IOWR(NVHOST_PVA_IOCTL_MAGIC, 6, struct pva_ioctl_vpu_func_table)
+#define PVA_IOCTL_SET_RATE      \
+        _IOWR(NVHOST_PVA_IOCTL_MAGIC, 7, struct pva_ioctl_rate)
+#define PVA_IOCTL_GET_RATE      \
+        _IOWR(NVHOST_PVA_IOCTL_MAGIC, 8, struct pva_ioctl_rate)
 
 
-#define NVHOST_PVA_IOCTL_LAST _IOC_NR(PVA_IOCTL_COPY_VPU_FUNCTION_TABLE)
+#define NVHOST_PVA_IOCTL_LAST _IOC_NR(PVA_IOCTL_GET_RATE)
 #define NVHOST_PVA_IOCTL_MAX_ARG_SIZE sizeof(struct pva_characteristics_req)
 
 #endif /* __LINUX_NVHOST_PVA_IOCTL_H */