From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH v6 10/14] memory: tegra: Add EMC scaling sequence code for Tegra210 Date: Fri, 10 Apr 2020 17:18:51 +0300 Message-ID: <682c661d-ea3a-7b9a-42f0-d5473b969aa2@gmail.com> References: <20200409175238.3586487-1-thierry.reding@gmail.com> <20200409175238.3586487-11-thierry.reding@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200409175238.3586487-11-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Content-Language: en-US Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thierry Reding , Rob Herring Cc: Jon Hunter , Michael Turquette , Stephen Boyd , Joseph Lo , linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-tegra@vger.kernel.org 09.04.2020 20:52, Thierry Reding пишет: ... > +static void tegra210_emc_r21021_set_clock(struct tegra210_emc *emc, u32 clksrc) > +{ > + /* > + * This is the timing table for the source frequency. It does _not_ > + * necessarily correspond to the actual timing values in the EMC at the > + * moment. If the boot BCT differs from the table then this can happen. > + * However, we need it for accessing the dram_timings (which are not > + * really registers) array for the current frequency. > + */ > + u32 tmp, cya_allow_ref_cc = 0, ref_b4_sref_en = 0, cya_issue_pc_ref = 0; > + struct tegra210_emc_timing *fake, *last = emc->last, *next = emc->next; > + u32 bg_regulator_switch_complete_wait_clks, bg_regulator_mode_change; > + u32 opt_zcal_en_cc, opt_do_sw_qrst = 1, opt_dvfs_mode, opt_dll_mode; > + u32 emc_zcal_wait_cnt_old, emc_zcal_wait_cnt_new, emc_dbg_active; > + u32 opt_cc_short_zcal = 1, opt_short_zcal = 1, opt_war_200024907; > + u32 tRTM, RP_war, R2P_war, TRPab_war, deltaTWATM, W2P_war, tRPST; > + u32 adel = 0, compensate_trimmer_applicable = 0, mrw_req, value; > + unsigned long next_timing_rate_mhz = next->rate / 1000, delay; > + u32 tZQCAL_lpddr4 = 1000000, zq_wait_long, shared_zq_resistor; > + s32 zq_latch_dvfs_wait_time, tZQCAL_lpddr4_fc_adj, nRTP; > + u32 tFC_lpddr4 = 1000 * next->dram_timings[T_FC_LPDDR4]; > + u32 emc_auto_cal_config, auto_cal_en, mr13_catr_enable; > + u32 zq_op, zcal_wait_time_clocks, zcal_wait_time_ps; > + u32 emc_cfg, emc_sel_dpd_ctrl, emc_zcal_interval; > + int next_push, next_dq_e_ivref, next_dqs_e_ivref; > + u32 mr13_flip_fspwr, mr13_flip_fspop, is_lpddr3; > + u32 enable_bglp_regulator, enable_bg_regulator; > + u32 emc_dbg_o, emc_cfg_pipe_clk_o, emc_pin_o; > + u32 ramp_up_wait = 0, ramp_down_wait = 0; > + u32 save_restore_clkstop_pd = 1, dll_out; > + u32 ref_delay_mult, ref_delay, dram_type; > + static u32 fsp_for_next_freq; > + /* In picoseconds. */ > + u32 source_clock_period, destination_clock_period; > + u32 zqcal_before_cc_cutoff = 2400; > + unsigned int i; What about to try to replace this massive egyptian construction with a single "u32 val;" ? ... > + emc_readl(emc, EMC_CFG); > + emc_auto_cal_config = emc_readl(emc, EMC_AUTO_CAL_CONFIG); And remove all the "dummy" variable assigns in the code? ... > emc_auto_cal_config = next->emc_auto_cal_config; ...> + emc_zcal_interval = 0; And replace all "constant" variables with a raw value in place in the code?