ARM: OMAP2+: gpmc: generic timing calculation
[deliverable/linux.git] / arch / arm / mach-omap2 / gpmc.c
index 5619d1b486684cb62011e52fd6ea5a58577271aa..65468f6d7f0e62382ee6df3c16fcb2cad5eb054e 100644 (file)
@@ -230,6 +230,18 @@ unsigned int gpmc_round_ns_to_ticks(unsigned int time_ns)
        return ticks * gpmc_get_fclk_period() / 1000;
 }
 
+static unsigned int gpmc_ticks_to_ps(unsigned int ticks)
+{
+       return ticks * gpmc_get_fclk_period();
+}
+
+static unsigned int gpmc_round_ps_to_ticks(unsigned int time_ps)
+{
+       unsigned long ticks = gpmc_ps_to_ticks(time_ps);
+
+       return ticks * gpmc_get_fclk_period();
+}
+
 static inline void gpmc_cs_modify_reg(int cs, int reg, u32 mask, bool value)
 {
        u32 l;
@@ -796,6 +808,319 @@ static int __devinit gpmc_mem_init(void)
        return 0;
 }
 
+static u32 gpmc_round_ps_to_sync_clk(u32 time_ps, u32 sync_clk)
+{
+       u32 temp;
+       int div;
+
+       div = gpmc_calc_divider(sync_clk);
+       temp = gpmc_ps_to_ticks(time_ps);
+       temp = (temp + div - 1) / div;
+       return gpmc_ticks_to_ps(temp * div);
+}
+
+/* XXX: can the cycles be avoided ? */
+static int gpmc_calc_sync_read_timings(struct gpmc_timings *gpmc_t,
+                               struct gpmc_device_timings *dev_t)
+{
+       bool mux = dev_t->mux;
+       u32 temp;
+
+       /* adv_rd_off */
+       temp = dev_t->t_avdp_r;
+       /* XXX: mux check required ? */
+       if (mux) {
+               /* XXX: t_avdp not to be required for sync, only added for tusb
+                * this indirectly necessitates requirement of t_avdp_r and
+                * t_avdp_w instead of having a single t_avdp
+                */
+               temp = max_t(u32, temp, gpmc_t->clk_activation + dev_t->t_avdh);
+               temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+       }
+       gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);
+
+       /* oe_on */
+       temp = dev_t->t_oeasu; /* XXX: remove this ? */
+       if (mux) {
+               temp = max_t(u32, temp, gpmc_t->clk_activation + dev_t->t_ach);
+               temp = max_t(u32, temp, gpmc_t->adv_rd_off +
+                               gpmc_ticks_to_ps(dev_t->cyc_aavdh_oe));
+       }
+       gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);
+
+       /* access */
+       /* XXX: any scope for improvement ?, by combining oe_on
+        * and clk_activation, need to check whether
+        * access = clk_activation + round to sync clk ?
+        */
+       temp = max_t(u32, dev_t->t_iaa, dev_t->cyc_iaa * gpmc_t->sync_clk);
+       temp += gpmc_t->clk_activation;
+       if (dev_t->cyc_oe)
+               temp = max_t(u32, temp, gpmc_t->oe_on +
+                               gpmc_ticks_to_ps(dev_t->cyc_oe));
+       gpmc_t->access = gpmc_round_ps_to_ticks(temp);
+
+       gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
+       gpmc_t->cs_rd_off = gpmc_t->oe_off;
+
+       /* rd_cycle */
+       temp = max_t(u32, dev_t->t_cez_r, dev_t->t_oez);
+       temp = gpmc_round_ps_to_sync_clk(temp, gpmc_t->sync_clk) +
+                                                       gpmc_t->access;
+       /* XXX: barter t_ce_rdyz with t_cez_r ? */
+       if (dev_t->t_ce_rdyz)
+               temp = max_t(u32, temp, gpmc_t->cs_rd_off + dev_t->t_ce_rdyz);
+       gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);
+
+       return 0;
+}
+
+static int gpmc_calc_sync_write_timings(struct gpmc_timings *gpmc_t,
+                               struct gpmc_device_timings *dev_t)
+{
+       bool mux = dev_t->mux;
+       u32 temp;
+
+       /* adv_wr_off */
+       temp = dev_t->t_avdp_w;
+       if (mux) {
+               temp = max_t(u32, temp,
+                       gpmc_t->clk_activation + dev_t->t_avdh);
+               temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+       }
+       gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);
+
+       /* wr_data_mux_bus */
+       temp = max_t(u32, dev_t->t_weasu,
+                       gpmc_t->clk_activation + dev_t->t_rdyo);
+       /* XXX: shouldn't mux be kept as a whole for wr_data_mux_bus ?,
+        * and in that case remember to handle we_on properly
+        */
+       if (mux) {
+               temp = max_t(u32, temp,
+                       gpmc_t->adv_wr_off + dev_t->t_aavdh);
+               temp = max_t(u32, temp, gpmc_t->adv_wr_off +
+                               gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
+       }
+       gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);
+
+       /* we_on */
+       if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
+               gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
+       else
+               gpmc_t->we_on = gpmc_t->wr_data_mux_bus;
+
+       /* wr_access */
+       /* XXX: gpmc_capability check reqd ? , even if not, will not harm */
+       gpmc_t->wr_access = gpmc_t->access;
+
+       /* we_off */
+       temp = gpmc_t->we_on + dev_t->t_wpl;
+       temp = max_t(u32, temp,
+                       gpmc_t->wr_access + gpmc_ticks_to_ps(1));
+       temp = max_t(u32, temp,
+               gpmc_t->we_on + gpmc_ticks_to_ps(dev_t->cyc_wpl));
+       gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);
+
+       gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
+                                                       dev_t->t_wph);
+
+       /* wr_cycle */
+       temp = gpmc_round_ps_to_sync_clk(dev_t->t_cez_w, gpmc_t->sync_clk);
+       temp += gpmc_t->wr_access;
+       /* XXX: barter t_ce_rdyz with t_cez_w ? */
+       if (dev_t->t_ce_rdyz)
+               temp = max_t(u32, temp,
+                                gpmc_t->cs_wr_off + dev_t->t_ce_rdyz);
+       gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);
+
+       return 0;
+}
+
+static int gpmc_calc_async_read_timings(struct gpmc_timings *gpmc_t,
+                               struct gpmc_device_timings *dev_t)
+{
+       bool mux = dev_t->mux;
+       u32 temp;
+
+       /* adv_rd_off */
+       temp = dev_t->t_avdp_r;
+       if (mux)
+               temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+       gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);
+
+       /* oe_on */
+       temp = dev_t->t_oeasu;
+       if (mux)
+               temp = max_t(u32, temp,
+                       gpmc_t->adv_rd_off + dev_t->t_aavdh);
+       gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);
+
+       /* access */
+       temp = max_t(u32, dev_t->t_iaa, /* XXX: remove t_iaa in async ? */
+                               gpmc_t->oe_on + dev_t->t_oe);
+       temp = max_t(u32, temp,
+                               gpmc_t->cs_on + dev_t->t_ce);
+       temp = max_t(u32, temp,
+                               gpmc_t->adv_on + dev_t->t_aa);
+       gpmc_t->access = gpmc_round_ps_to_ticks(temp);
+
+       gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
+       gpmc_t->cs_rd_off = gpmc_t->oe_off;
+
+       /* rd_cycle */
+       temp = max_t(u32, dev_t->t_rd_cycle,
+                       gpmc_t->cs_rd_off + dev_t->t_cez_r);
+       temp = max_t(u32, temp, gpmc_t->oe_off + dev_t->t_oez);
+       gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);
+
+       return 0;
+}
+
+static int gpmc_calc_async_write_timings(struct gpmc_timings *gpmc_t,
+                               struct gpmc_device_timings *dev_t)
+{
+       bool mux = dev_t->mux;
+       u32 temp;
+
+       /* adv_wr_off */
+       temp = dev_t->t_avdp_w;
+       if (mux)
+               temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+       gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);
+
+       /* wr_data_mux_bus */
+       temp = dev_t->t_weasu;
+       if (mux) {
+               temp = max_t(u32, temp, gpmc_t->adv_wr_off + dev_t->t_aavdh);
+               temp = max_t(u32, temp, gpmc_t->adv_wr_off +
+                               gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
+       }
+       gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);
+
+       /* we_on */
+       if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
+               gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
+       else
+               gpmc_t->we_on = gpmc_t->wr_data_mux_bus;
+
+       /* we_off */
+       temp = gpmc_t->we_on + dev_t->t_wpl;
+       gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);
+
+       gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
+                                                       dev_t->t_wph);
+
+       /* wr_cycle */
+       temp = max_t(u32, dev_t->t_wr_cycle,
+                               gpmc_t->cs_wr_off + dev_t->t_cez_w);
+       gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);
+
+       return 0;
+}
+
+static int gpmc_calc_sync_common_timings(struct gpmc_timings *gpmc_t,
+                       struct gpmc_device_timings *dev_t)
+{
+       u32 temp;
+
+       gpmc_t->sync_clk = gpmc_calc_divider(dev_t->clk) *
+                                               gpmc_get_fclk_period();
+
+       gpmc_t->page_burst_access = gpmc_round_ps_to_sync_clk(
+                                       dev_t->t_bacc,
+                                       gpmc_t->sync_clk);
+
+       temp = max_t(u32, dev_t->t_ces, dev_t->t_avds);
+       gpmc_t->clk_activation = gpmc_round_ps_to_ticks(temp);
+
+       if (gpmc_calc_divider(gpmc_t->sync_clk) != 1)
+               return 0;
+
+       if (dev_t->ce_xdelay)
+               gpmc_t->bool_timings.cs_extra_delay = true;
+       if (dev_t->avd_xdelay)
+               gpmc_t->bool_timings.adv_extra_delay = true;
+       if (dev_t->oe_xdelay)
+               gpmc_t->bool_timings.oe_extra_delay = true;
+       if (dev_t->we_xdelay)
+               gpmc_t->bool_timings.we_extra_delay = true;
+
+       return 0;
+}
+
+static int gpmc_calc_common_timings(struct gpmc_timings *gpmc_t,
+                       struct gpmc_device_timings *dev_t)
+{
+       u32 temp;
+
+       /* cs_on */
+       gpmc_t->cs_on = gpmc_round_ps_to_ticks(dev_t->t_ceasu);
+
+       /* adv_on */
+       temp = dev_t->t_avdasu;
+       if (dev_t->t_ce_avd)
+               temp = max_t(u32, temp,
+                               gpmc_t->cs_on + dev_t->t_ce_avd);
+       gpmc_t->adv_on = gpmc_round_ps_to_ticks(temp);
+
+       if (dev_t->sync_write || dev_t->sync_read)
+               gpmc_calc_sync_common_timings(gpmc_t, dev_t);
+
+       return 0;
+}
+
+/* TODO: remove this function once all peripherals are confirmed to
+ * work with generic timing. Simultaneously gpmc_cs_set_timings()
+ * has to be modified to handle timings in ps instead of ns
+*/
+static void gpmc_convert_ps_to_ns(struct gpmc_timings *t)
+{
+       t->cs_on /= 1000;
+       t->cs_rd_off /= 1000;
+       t->cs_wr_off /= 1000;
+       t->adv_on /= 1000;
+       t->adv_rd_off /= 1000;
+       t->adv_wr_off /= 1000;
+       t->we_on /= 1000;
+       t->we_off /= 1000;
+       t->oe_on /= 1000;
+       t->oe_off /= 1000;
+       t->page_burst_access /= 1000;
+       t->access /= 1000;
+       t->rd_cycle /= 1000;
+       t->wr_cycle /= 1000;
+       t->bus_turnaround /= 1000;
+       t->cycle2cycle_delay /= 1000;
+       t->wait_monitoring /= 1000;
+       t->clk_activation /= 1000;
+       t->wr_access /= 1000;
+       t->wr_data_mux_bus /= 1000;
+}
+
+int gpmc_calc_timings(struct gpmc_timings *gpmc_t,
+                       struct gpmc_device_timings *dev_t)
+{
+       memset(gpmc_t, 0, sizeof(*gpmc_t));
+
+       gpmc_calc_common_timings(gpmc_t, dev_t);
+
+       if (dev_t->sync_read)
+               gpmc_calc_sync_read_timings(gpmc_t, dev_t);
+       else
+               gpmc_calc_async_read_timings(gpmc_t, dev_t);
+
+       if (dev_t->sync_write)
+               gpmc_calc_sync_write_timings(gpmc_t, dev_t);
+       else
+               gpmc_calc_async_write_timings(gpmc_t, dev_t);
+
+       /* TODO: remove, see function definition */
+       gpmc_convert_ps_to_ns(gpmc_t);
+
+       return 0;
+}
+
 static __devinit int gpmc_probe(struct platform_device *pdev)
 {
        int rc;
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