*/
#include <common.h>
+#include <clk.h>
#include <dm.h>
#include <i2c.h>
#include <pci.h>
#include <asm/io.h>
#include "designware_i2c.h"
-struct dw_scl_sda_cfg {
- u32 ss_hcnt;
- u32 fs_hcnt;
- u32 ss_lcnt;
- u32 fs_lcnt;
- u32 sda_hold;
-};
-
-#ifdef CONFIG_X86
-/* BayTrail HCNT/LCNT/SDA hold time */
-static struct dw_scl_sda_cfg byt_config = {
- .ss_hcnt = 0x200,
- .fs_hcnt = 0x55,
- .ss_lcnt = 0x200,
- .fs_lcnt = 0x99,
- .sda_hold = 0x6,
-};
-#endif
-
-struct dw_i2c {
- struct i2c_regs *regs;
- struct dw_scl_sda_cfg *scl_sda_cfg;
- struct reset_ctl_bulk resets;
-};
-
#ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{
}
#endif
+/* High and low times in different speed modes (in ns) */
+enum {
+ /* SDA Hold Time */
+ DEFAULT_SDA_HOLD_TIME = 300,
+};
+
+/**
+ * calc_counts() - Convert a period to a number of IC clk cycles
+ *
+ * @ic_clk: Input clock in Hz
+ * @period_ns: Period to represent, in ns
+ * @return calculated count
+ */
+static uint calc_counts(uint ic_clk, uint period_ns)
+{
+ return DIV_ROUND_UP(ic_clk / 1000 * period_ns, NANO_TO_KILO);
+}
+
+/**
+ * struct i2c_mode_info - Information about an I2C speed mode
+ *
+ * Each speed mode has its own characteristics. This struct holds these to aid
+ * calculations in dw_i2c_calc_timing().
+ *
+ * @speed: Speed in Hz
+ * @min_scl_lowtime_ns: Minimum value for SCL low period in ns
+ * @min_scl_hightime_ns: Minimum value for SCL high period in ns
+ * @def_rise_time_ns: Default rise time in ns
+ * @def_fall_time_ns: Default fall time in ns
+ */
+struct i2c_mode_info {
+ int speed;
+ int min_scl_hightime_ns;
+ int min_scl_lowtime_ns;
+ int def_rise_time_ns;
+ int def_fall_time_ns;
+};
+
+static const struct i2c_mode_info info_for_mode[] = {
+ [IC_SPEED_MODE_STANDARD] = {
+ I2C_SPEED_STANDARD_RATE,
+ MIN_SS_SCL_HIGHTIME,
+ MIN_SS_SCL_LOWTIME,
+ 1000,
+ 300,
+ },
+ [IC_SPEED_MODE_FAST] = {
+ I2C_SPEED_FAST_RATE,
+ MIN_FS_SCL_HIGHTIME,
+ MIN_FS_SCL_LOWTIME,
+ 300,
+ 300,
+ },
+ [IC_SPEED_MODE_FAST_PLUS] = {
+ I2C_SPEED_FAST_PLUS_RATE,
+ MIN_FP_SCL_HIGHTIME,
+ MIN_FP_SCL_LOWTIME,
+ 260,
+ 500,
+ },
+ [IC_SPEED_MODE_HIGH] = {
+ I2C_SPEED_HIGH_RATE,
+ MIN_HS_SCL_HIGHTIME,
+ MIN_HS_SCL_LOWTIME,
+ 120,
+ 120,
+ },
+};
+
+/**
+ * dw_i2c_calc_timing() - Calculate the timings to use for a bus
+ *
+ * @priv: Bus private information (NULL if not using driver model)
+ * @mode: Speed mode to use
+ * @ic_clk: IC clock speed in Hz
+ * @spk_cnt: Spike-suppression count
+ * @config: Returns value to use
+ * @return 0 if OK, -EINVAL if the calculation failed due to invalid data
+ */
+static int dw_i2c_calc_timing(struct dw_i2c *priv, enum i2c_speed_mode mode,
+ int ic_clk, int spk_cnt,
+ struct dw_i2c_speed_config *config)
+{
+ int fall_cnt, rise_cnt, min_tlow_cnt, min_thigh_cnt;
+ int hcnt, lcnt, period_cnt, diff, tot;
+ int sda_hold_time_ns, scl_rise_time_ns, scl_fall_time_ns;
+ const struct i2c_mode_info *info;
+
+ /*
+ * Find the period, rise, fall, min tlow, and min thigh in terms of
+ * counts of the IC clock
+ */
+ info = &info_for_mode[mode];
+ period_cnt = ic_clk / info->speed;
+ scl_rise_time_ns = priv && priv->scl_rise_time_ns ?
+ priv->scl_rise_time_ns : info->def_rise_time_ns;
+ scl_fall_time_ns = priv && priv->scl_fall_time_ns ?
+ priv->scl_fall_time_ns : info->def_fall_time_ns;
+ rise_cnt = calc_counts(ic_clk, scl_rise_time_ns);
+ fall_cnt = calc_counts(ic_clk, scl_fall_time_ns);
+ min_tlow_cnt = calc_counts(ic_clk, info->min_scl_lowtime_ns);
+ min_thigh_cnt = calc_counts(ic_clk, info->min_scl_hightime_ns);
+
+ debug("dw_i2c: period %d rise %d fall %d tlow %d thigh %d spk %d\n",
+ period_cnt, rise_cnt, fall_cnt, min_tlow_cnt, min_thigh_cnt,
+ spk_cnt);
+
+ /*
+ * Back-solve for hcnt and lcnt according to the following equations:
+ * SCL_High_time = [(HCNT + IC_*_SPKLEN + 7) * ic_clk] + SCL_Fall_time
+ * SCL_Low_time = [(LCNT + 1) * ic_clk] - SCL_Fall_time + SCL_Rise_time
+ */
+ hcnt = min_thigh_cnt - fall_cnt - 7 - spk_cnt;
+ lcnt = min_tlow_cnt - rise_cnt + fall_cnt - 1;
+
+ if (hcnt < 0 || lcnt < 0) {
+ debug("dw_i2c: bad counts. hcnt = %d lcnt = %d\n", hcnt, lcnt);
+ return -EINVAL;
+ }
+
+ /*
+ * Now add things back up to ensure the period is hit. If it is off,
+ * split the difference and bias to lcnt for remainder
+ */
+ tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1;
+
+ if (tot < period_cnt) {
+ diff = (period_cnt - tot) / 2;
+ hcnt += diff;
+ lcnt += diff;
+ tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1;
+ lcnt += period_cnt - tot;
+ }
+
+ config->scl_lcnt = lcnt;
+ config->scl_hcnt = hcnt;
+
+ /* Use internal default unless other value is specified */
+ sda_hold_time_ns = priv && priv->sda_hold_time_ns ?
+ priv->sda_hold_time_ns : DEFAULT_SDA_HOLD_TIME;
+ config->sda_hold = calc_counts(ic_clk, sda_hold_time_ns);
+
+ debug("dw_i2c: hcnt = %d lcnt = %d sda hold = %d\n", hcnt, lcnt,
+ config->sda_hold);
+
+ return 0;
+}
+
/*
* i2c_set_bus_speed - Set the i2c speed
* @speed: required i2c speed
*
* Set the i2c speed.
*/
-static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base,
- struct dw_scl_sda_cfg *scl_sda_cfg,
- unsigned int speed)
+static unsigned int __dw_i2c_set_bus_speed(struct dw_i2c *priv,
+ struct i2c_regs *i2c_base,
+ unsigned int speed,
+ unsigned int bus_clk)
{
+ const struct dw_scl_sda_cfg *scl_sda_cfg = NULL;
+ struct dw_i2c_speed_config config;
+ enum i2c_speed_mode i2c_spd;
unsigned int cntl;
- unsigned int hcnt, lcnt;
- int i2c_spd;
+ unsigned int ena;
+ int spk_cnt;
+ int ret;
- if (speed >= I2C_MAX_SPEED)
- i2c_spd = IC_SPEED_MODE_MAX;
- else if (speed >= I2C_FAST_SPEED)
+ if (priv)
+ scl_sda_cfg = priv->scl_sda_cfg;
+ /* Allow high speed if there is no config, or the config allows it */
+ if (speed >= I2C_SPEED_HIGH_RATE &&
+ (!scl_sda_cfg || scl_sda_cfg->has_high_speed))
+ i2c_spd = IC_SPEED_MODE_HIGH;
+ else if (speed >= I2C_SPEED_FAST_RATE)
+ i2c_spd = IC_SPEED_MODE_FAST_PLUS;
+ else if (speed >= I2C_SPEED_FAST_PLUS_RATE)
i2c_spd = IC_SPEED_MODE_FAST;
else
i2c_spd = IC_SPEED_MODE_STANDARD;
+ /* Get enable setting for restore later */
+ ena = readl(&i2c_base->ic_enable) & IC_ENABLE_0B;
+
/* to set speed cltr must be disabled */
dw_i2c_enable(i2c_base, false);
cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK));
- switch (i2c_spd) {
-#ifndef CONFIG_X86 /* No High-speed for BayTrail yet */
- case IC_SPEED_MODE_MAX:
- cntl |= IC_CON_SPD_SS;
- if (scl_sda_cfg) {
- hcnt = scl_sda_cfg->fs_hcnt;
- lcnt = scl_sda_cfg->fs_lcnt;
+ /* Get the proper spike-suppression count based on target speed */
+ if (!priv || !priv->has_spk_cnt)
+ spk_cnt = 0;
+ else if (i2c_spd >= IC_SPEED_MODE_HIGH)
+ spk_cnt = readl(&i2c_base->hs_spklen);
+ else
+ spk_cnt = readl(&i2c_base->fs_spklen);
+ if (scl_sda_cfg) {
+ config.sda_hold = scl_sda_cfg->sda_hold;
+ if (i2c_spd == IC_SPEED_MODE_STANDARD) {
+ config.scl_hcnt = scl_sda_cfg->ss_hcnt;
+ config.scl_lcnt = scl_sda_cfg->ss_lcnt;
} else {
- hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
- lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
+ config.scl_hcnt = scl_sda_cfg->fs_hcnt;
+ config.scl_lcnt = scl_sda_cfg->fs_lcnt;
}
- writel(hcnt, &i2c_base->ic_hs_scl_hcnt);
- writel(lcnt, &i2c_base->ic_hs_scl_lcnt);
- break;
-#endif
+ } else {
+ ret = dw_i2c_calc_timing(priv, i2c_spd, bus_clk, spk_cnt,
+ &config);
+ if (ret)
+ return log_msg_ret("gen_confg", ret);
+ }
+ switch (i2c_spd) {
+ case IC_SPEED_MODE_HIGH:
+ cntl |= IC_CON_SPD_SS;
+ writel(config.scl_hcnt, &i2c_base->ic_hs_scl_hcnt);
+ writel(config.scl_lcnt, &i2c_base->ic_hs_scl_lcnt);
+ break;
case IC_SPEED_MODE_STANDARD:
cntl |= IC_CON_SPD_SS;
- if (scl_sda_cfg) {
- hcnt = scl_sda_cfg->ss_hcnt;
- lcnt = scl_sda_cfg->ss_lcnt;
- } else {
- hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
- lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
- }
- writel(hcnt, &i2c_base->ic_ss_scl_hcnt);
- writel(lcnt, &i2c_base->ic_ss_scl_lcnt);
+ writel(config.scl_hcnt, &i2c_base->ic_ss_scl_hcnt);
+ writel(config.scl_lcnt, &i2c_base->ic_ss_scl_lcnt);
break;
-
+ case IC_SPEED_MODE_FAST_PLUS:
case IC_SPEED_MODE_FAST:
default:
cntl |= IC_CON_SPD_FS;
- if (scl_sda_cfg) {
- hcnt = scl_sda_cfg->fs_hcnt;
- lcnt = scl_sda_cfg->fs_lcnt;
- } else {
- hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
- lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
- }
- writel(hcnt, &i2c_base->ic_fs_scl_hcnt);
- writel(lcnt, &i2c_base->ic_fs_scl_lcnt);
+ writel(config.scl_hcnt, &i2c_base->ic_fs_scl_hcnt);
+ writel(config.scl_lcnt, &i2c_base->ic_fs_scl_lcnt);
break;
}
writel(cntl, &i2c_base->ic_con);
/* Configure SDA Hold Time if required */
- if (scl_sda_cfg)
- writel(scl_sda_cfg->sda_hold, &i2c_base->ic_sda_hold);
+ if (config.sda_hold)
+ writel(config.sda_hold, &i2c_base->ic_sda_hold);
- /* Enable back i2c now speed set */
- dw_i2c_enable(i2c_base, true);
+ /* Restore back i2c now speed set */
+ if (ena == IC_ENABLE_0B)
+ dw_i2c_enable(i2c_base, true);
return 0;
}
writel(IC_TX_TL, &i2c_base->ic_tx_tl);
writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
#ifndef CONFIG_DM_I2C
- __dw_i2c_set_bus_speed(i2c_base, NULL, speed);
+ __dw_i2c_set_bus_speed(NULL, i2c_base, speed, IC_CLK);
writel(slaveaddr, &i2c_base->ic_sar);
#endif
unsigned int speed)
{
adap->speed = speed;
- return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed);
+ return __dw_i2c_set_bus_speed(NULL, i2c_get_base(adap), speed, IC_CLK);
}
static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
struct dw_i2c *i2c = dev_get_priv(bus);
+ ulong rate;
- return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed);
+#if CONFIG_IS_ENABLED(CLK)
+ rate = clk_get_rate(&i2c->clk);
+ if (IS_ERR_VALUE(rate))
+ return -EINVAL;
+#else
+ rate = IC_CLK;
+#endif
+ return __dw_i2c_set_bus_speed(i2c, i2c->regs, speed, rate);
}
static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr,
return ret;
}
-static int designware_i2c_probe(struct udevice *bus)
+int designware_i2c_ofdata_to_platdata(struct udevice *bus)
{
struct dw_i2c *priv = dev_get_priv(bus);
- int ret;
- if (device_is_on_pci_bus(bus)) {
-#ifdef CONFIG_DM_PCI
- /* Save base address from PCI BAR */
- priv->regs = (struct i2c_regs *)
- dm_pci_map_bar(bus, PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
-#ifdef CONFIG_X86
- /* Use BayTrail specific timing values */
- priv->scl_sda_cfg = &byt_config;
-#endif
-#endif
- } else {
+ if (!priv->regs)
priv->regs = (struct i2c_regs *)devfdt_get_addr_ptr(bus);
- }
+ dev_read_u32(bus, "i2c-scl-rising-time-ns", &priv->scl_rise_time_ns);
+ dev_read_u32(bus, "i2c-scl-falling-time-ns", &priv->scl_fall_time_ns);
+ dev_read_u32(bus, "i2c-sda-hold-time-ns", &priv->sda_hold_time_ns);
+
+ return 0;
+}
+
+int designware_i2c_probe(struct udevice *bus)
+{
+ struct dw_i2c *priv = dev_get_priv(bus);
+ int ret;
ret = reset_get_bulk(bus, &priv->resets);
if (ret)
else
reset_deassert_bulk(&priv->resets);
- return __dw_i2c_init(priv->regs, 0, 0);
-}
+#if CONFIG_IS_ENABLED(CLK)
+ ret = clk_get_by_index(bus, 0, &priv->clk);
+ if (ret)
+ return ret;
-static int designware_i2c_remove(struct udevice *dev)
-{
- struct dw_i2c *priv = dev_get_priv(dev);
+ ret = clk_enable(&priv->clk);
+ if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
+ clk_free(&priv->clk);
+ dev_err(bus, "failed to enable clock\n");
+ return ret;
+ }
+#endif
- return reset_release_bulk(&priv->resets);
+ return __dw_i2c_init(priv->regs, 0, 0);
}
-static int designware_i2c_bind(struct udevice *dev)
+int designware_i2c_remove(struct udevice *dev)
{
- static int num_cards;
- char name[20];
+ struct dw_i2c *priv = dev_get_priv(dev);
- /* Create a unique device name for PCI type devices */
- if (device_is_on_pci_bus(dev)) {
- /*
- * ToDo:
- * Setting req_seq in the driver is probably not recommended.
- * But without a DT alias the number is not configured. And
- * using this driver is impossible for PCIe I2C devices.
- * This can be removed, once a better (correct) way for this
- * is found and implemented.
- */
- dev->req_seq = num_cards;
- sprintf(name, "i2c_designware#%u", num_cards++);
- device_set_name(dev, name);
- }
+#if CONFIG_IS_ENABLED(CLK)
+ clk_disable(&priv->clk);
+ clk_free(&priv->clk);
+#endif
- return 0;
+ return reset_release_bulk(&priv->resets);
}
-static const struct dm_i2c_ops designware_i2c_ops = {
+const struct dm_i2c_ops designware_i2c_ops = {
.xfer = designware_i2c_xfer,
.probe_chip = designware_i2c_probe_chip,
.set_bus_speed = designware_i2c_set_bus_speed,
.name = "i2c_designware",
.id = UCLASS_I2C,
.of_match = designware_i2c_ids,
- .bind = designware_i2c_bind,
+ .ofdata_to_platdata = designware_i2c_ofdata_to_platdata,
.probe = designware_i2c_probe,
.priv_auto_alloc_size = sizeof(struct dw_i2c),
.remove = designware_i2c_remove,
- .flags = DM_FLAG_OS_PREPARE,
+ .flags = DM_FLAG_OS_PREPARE,
.ops = &designware_i2c_ops,
};
-#ifdef CONFIG_X86
-static struct pci_device_id designware_pci_supported[] = {
- /* Intel BayTrail has 7 I2C controller located on the PCI bus */
- { PCI_VDEVICE(INTEL, 0x0f41) },
- { PCI_VDEVICE(INTEL, 0x0f42) },
- { PCI_VDEVICE(INTEL, 0x0f43) },
- { PCI_VDEVICE(INTEL, 0x0f44) },
- { PCI_VDEVICE(INTEL, 0x0f45) },
- { PCI_VDEVICE(INTEL, 0x0f46) },
- { PCI_VDEVICE(INTEL, 0x0f47) },
- {},
-};
-
-U_BOOT_PCI_DEVICE(i2c_designware, designware_pci_supported);
-#endif
-
#endif /* CONFIG_DM_I2C */