gpu: nvgpu: vgpu: add devfreq support

Add devfreq governor support in order to allow frequency scaling
in virtualization config. GPU clock frequency operations are
re-directed to the server over RPC.

Bug 200237433

Change-Id: I1c8e565a4fff36d3456dc72ebb20795b7822650e
Signed-off-by: Sachit Kadle <skadle@nvidia.com>
Reviewed-on: http://git-master/r/1295542
(cherry picked from commit d5c956fc06697eda3829c67cb22987e538213b29)
Reviewed-on: http://git-master/r/1280968
(cherry picked from commit 25e2b3cf7cb5559a6849c0024d42c157564a9be2)
Reviewed-on: http://git-master/r/1321835
(cherry picked from commit f871b52fd3f553d6b6375a3c848fbca272ed8e29)
Reviewed-on: http://git-master/r/1313468
Tested-by: Aparna Das <aparnad@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: Richard Zhao <rizhao@nvidia.com>
GVS: Gerrit_Virtual_Submit

1 files changed, 130 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/vgpu/clk_vgpu.c b/drivers/gpu/nvgpu/vgpu/clk_vgpu.c
new file mode 100644
index 00000000..fe5533b6
--- /dev/null
+++ b/drivers/gpu/nvgpu/vgpu/clk_vgpu.c
@@ -0,0 +1,130 @@
+/*
+ * Virtualized GPU Clock Interface
+ *
+ * Copyright (c) 2017, 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,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include "vgpu/vgpu.h"
+#include "vgpu/clk_vgpu.h"
+
+static unsigned long
+vgpu_freq_table[TEGRA_VGPU_GPU_FREQ_TABLE_SIZE];
+
+static unsigned long vgpu_clk_get_rate(struct gk20a *g, u32 api_domain)
+{
+        struct tegra_vgpu_cmd_msg msg = {};
+        struct tegra_vgpu_gpu_clk_rate_params *p = &msg.params.gpu_clk_rate;
+        int err;
+        unsigned long ret = 0;
+
+        gk20a_dbg_fn("");
+
+        switch (api_domain) {
+        case CTRL_CLK_DOMAIN_GPCCLK:
+                msg.cmd = TEGRA_VGPU_CMD_GET_GPU_CLK_RATE;
+                msg.handle = vgpu_get_handle(g);
+                err = vgpu_comm_sendrecv(&msg, sizeof(msg), sizeof(msg));
+                err = err ? err : msg.ret;
+                if (err)
+                        nvgpu_err(g, "%s failed - %d", __func__, err);
+                else
+                        /* return frequency in Hz */
+                        ret = p->rate * 1000;
+                break;
+        case CTRL_CLK_DOMAIN_PWRCLK:
+                nvgpu_err(g, "unsupported clock: %u", api_domain);
+                break;
+        default:
+                nvgpu_err(g, "unknown clock: %u", api_domain);
+                break;
+        }
+
+        return ret;
+}
+
+static int vgpu_clk_set_rate(struct gk20a *g,
+                                u32 api_domain, unsigned long rate)
+{
+        struct tegra_vgpu_cmd_msg msg = {};
+        struct tegra_vgpu_gpu_clk_rate_params *p = &msg.params.gpu_clk_rate;
+        int err = -EINVAL;
+
+        gk20a_dbg_fn("");
+
+        switch (api_domain) {
+        case CTRL_CLK_DOMAIN_GPCCLK:
+                msg.cmd = TEGRA_VGPU_CMD_SET_GPU_CLK_RATE;
+                msg.handle = vgpu_get_handle(g);
+
+                /* server dvfs framework requires frequency in kHz */
+                p->rate = (u32)(rate / 1000);
+                err = vgpu_comm_sendrecv(&msg, sizeof(msg), sizeof(msg));
+                err = err ? err : msg.ret;
+                if (err)
+                        nvgpu_err(g, "%s failed - %d", __func__, err);
+                break;
+        case CTRL_CLK_DOMAIN_PWRCLK:
+                nvgpu_err(g, "unsupported clock: %u", api_domain);
+                break;
+        default:
+                nvgpu_err(g, "unknown clock: %u", api_domain);
+                break;
+        }
+
+        return err;
+}
+
+void vgpu_init_clk_support(struct gk20a *g)
+{
+        g->ops.clk.get_rate = vgpu_clk_get_rate;
+        g->ops.clk.set_rate = vgpu_clk_set_rate;
+}
+
+long vgpu_clk_round_rate(struct device *dev, unsigned long rate)
+{
+        /* server will handle frequency rounding */
+        return rate;
+}
+
+int vgpu_clk_get_freqs(struct device *dev,
+                unsigned long **freqs, int *num_freqs)
+{
+        struct gk20a_platform *platform = gk20a_get_platform(dev);
+        struct gk20a *g = platform->g;
+        struct tegra_vgpu_cmd_msg msg = {};
+        struct tegra_vgpu_get_gpu_freq_table_params *p =
+                                        &msg.params.get_gpu_freq_table;
+        unsigned int i;
+        int err;
+
+        gk20a_dbg_fn("");
+
+        msg.cmd = TEGRA_VGPU_CMD_GET_GPU_FREQ_TABLE;
+        msg.handle = vgpu_get_handle(g);
+
+        p->num_freqs = TEGRA_VGPU_GPU_FREQ_TABLE_SIZE;
+        err = vgpu_comm_sendrecv(&msg, sizeof(msg), sizeof(msg));
+        err = err ? err : msg.ret;
+        if (err) {
+                nvgpu_err(g, "%s failed - %d", __func__, err);
+                return err;
+        }
+
+        /* return frequency in Hz */
+        for (i = 0; i < p->num_freqs; i++)
+                vgpu_freq_table[i] = p->freqs[i] * 1000;
+
+        *freqs = vgpu_freq_table;
+        *num_freqs = p->num_freqs;
+
+        return 0;
+}