On Wed, Jun 1, 2016 at 6:35 PM, Lin Huang hl@rock-chips.com wrote:
there is dfi controller on rk3399 platform, it can monitor ddr load, register this controller to devfreq framework, and default to use simple_ondeamnd policy, and do ddr frequency scaling base on this result.
Signed-off-by: Lin Huang hl@rock-chips.com
drivers/devfreq/Kconfig | 2 +- drivers/devfreq/Makefile | 1 + drivers/devfreq/rockchip/Kconfig | 14 + drivers/devfreq/rockchip/Makefile | 2 + drivers/devfreq/rockchip/rk3399_dmc.c | 438 ++++++++++++++++++++++++++++++++ drivers/devfreq/rockchip/rockchip_dmc.c | 132 ++++++++++ include/soc/rockchip/rockchip_dmc.h | 44 ++++ 7 files changed, 632 insertions(+), 1 deletion(-) create mode 100644 drivers/devfreq/rockchip/Kconfig create mode 100644 drivers/devfreq/rockchip/Makefile create mode 100644 drivers/devfreq/rockchip/rk3399_dmc.c create mode 100644 drivers/devfreq/rockchip/rockchip_dmc.c create mode 100644 include/soc/rockchip/rockchip_dmc.h
/* check the rate we get whether correct */dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);if (dmcfreq->rate != target_rate) {dev_err(dev, "get wrong ddr frequency, Request freq %lu,\Current freq %lu\n", target_rate, dmcfreq->rate);regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,dmcfreq->volt);
Why do you need to check this and more importantly, why do you assume that dmvfreq->volt will be safe in this case? (what if the new dmcfreq->rate is larger than the old dmcfreq->rate after clk_get_rate?) Note that you didn't update dmcfreq->volt after clk_get_rate()
+EXPORT_SYMBOL_GPL(dmc_event); +EXPORT_SYMBOL_GPL(rockchip_dmc_enabled); +EXPORT_SYMBOL_GPL(rockchip_dmc_enable); +EXPORT_SYMBOL_GPL(rockchip_dmc_disable); +EXPORT_SYMBOL_GPL(dmc_register_notifier); +EXPORT_SYMBOL_GPL(dmc_unregister_notifier); +EXPORT_SYMBOL_GPL(rockchip_dmc_get); +EXPORT_SYMBOL_GPL(rockchip_dmc_put);
Do you really need to export all these device driver specific functions? Looks like a design flaw here.
Cheers, MyungJoo