As SPI support may be useful in the boot-flow, this adds support for configuring the SPI controller's clocks in the RK3368 clock driver.
Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com ---
Changes in v2: - added SPI clock setup
drivers/clk/rockchip/clk_rk3368.c | 132 ++++++++++++++++++++++++++++++-------- 1 file changed, 106 insertions(+), 26 deletions(-)
diff --git a/drivers/clk/rockchip/clk_rk3368.c b/drivers/clk/rockchip/clk_rk3368.c index d3f6c29..04f9b80 100644 --- a/drivers/clk/rockchip/clk_rk3368.c +++ b/drivers/clk/rockchip/clk_rk3368.c @@ -282,32 +282,6 @@ static ulong rk3368_mmc_set_clk(struct clk *clk, ulong rate) } #endif
-static ulong rk3368_clk_get_rate(struct clk *clk) -{ - struct rk3368_clk_priv *priv = dev_get_priv(clk->dev); - ulong rate = 0; - - debug("%s: id %ld\n", __func__, clk->id); - switch (clk->id) { - case PLL_CPLL: - rate = rkclk_pll_get_rate(priv->cru, CPLL); - break; - case PLL_GPLL: - rate = rkclk_pll_get_rate(priv->cru, GPLL); - break; -#if !IS_ENABLED(CONFIG_SPL_BUILD) || CONFIG_IS_ENABLED(MMC_SUPPORT) - case HCLK_SDMMC: - case HCLK_EMMC: - rate = rk3368_mmc_get_clk(priv->cru, clk->id); - break; -#endif - default: - return -ENOENT; - } - - return rate; -} - #if IS_ENABLED(CONFIG_TPL_BUILD) static ulong rk3368_ddr_set_clk(struct rk3368_cru *cru, ulong set_rate) { @@ -351,6 +325,109 @@ static ulong rk3368_gmac_set_clk(struct rk3368_cru *cru, } #endif
+/* + * RK3368 SPI clocks have a common divider-width (7 bits) and a single bit + * to select either CPLL or GPLL as the clock-parent. The location within + * the enclosing CLKSEL_CON (i.e. div_shift and sel_shift) are variable. + */ + +struct spi_clkreg { + uint8_t reg; /* CLKSEL_CON[reg] register in CRU */ + uint8_t div_shift; + uint8_t sel_shift; +}; + +/* + * The entries are numbered relative to their offset from SCLK_SPI0. + */ +static const struct spi_clkreg spi_clkregs[] = { + [0] = { .reg = 45, .div_shift = 0, .sel_shift = 7, }, + [1] = { .reg = 45, .div_shift = 8, .sel_shift = 15, }, + [2] = { .reg = 46, .div_shift = 8, .sel_shift = 15, }, +}; + +static inline u32 extract_bits(u32 val, unsigned width, unsigned shift) +{ + return (val >> shift) & ((1 << width) - 1); +} + +static ulong rk3368_spi_get_clk(struct rk3368_cru *cru, ulong clk_id) +{ + const struct spi_clkreg *spiclk = NULL; + u32 div, val; + + switch (clk_id) { + case SCLK_SPI0 ... SCLK_SPI2: + spiclk = &spi_clkregs[clk_id - SCLK_SPI0]; + break; + + default: + error("%s: SPI clk-id %ld not supported\n", __func__, clk_id); + return -EINVAL; + } + + val = readl(&cru->clksel_con[spiclk->reg]); + div = extract_bits(val, 7, spiclk->div_shift); + + debug("%s: div 0x%x\n", __func__, div); + return DIV_TO_RATE(GPLL_HZ, div); +} + +static ulong rk3368_spi_set_clk(struct rk3368_cru *cru, ulong clk_id, uint hz) +{ + const struct spi_clkreg *spiclk = NULL; + int src_clk_div; + + src_clk_div = RATE_TO_DIV(GPLL_HZ, hz); + assert(src_clk_div < 127); + + switch (clk_id) { + case SCLK_SPI0 ... SCLK_SPI2: + spiclk = &spi_clkregs[clk_id - SCLK_SPI0]; + break; + + default: + error("%s: SPI clk-id %ld not supported\n", __func__, clk_id); + return -EINVAL; + } + + rk_clrsetreg(&cru->clksel_con[spiclk->reg], + ((0x7f << spiclk->div_shift) | (0x1 << spiclk->sel_shift)), + ((src_clk_div << spiclk->div_shift) | + (1 /* TODO */ << spiclk->sel_shift))); + + return rk3368_spi_get_clk(cru, clk_id); +} + +static ulong rk3368_clk_get_rate(struct clk *clk) +{ + struct rk3368_clk_priv *priv = dev_get_priv(clk->dev); + ulong rate = 0; + + debug("%s: id %ld\n", __func__, clk->id); + switch (clk->id) { + case PLL_CPLL: + rate = rkclk_pll_get_rate(priv->cru, CPLL); + break; + case PLL_GPLL: + rate = rkclk_pll_get_rate(priv->cru, GPLL); + break; + case SCLK_SPI0 ... SCLK_SPI2: + rate = rk3368_spi_get_clk(priv->cru, clk->id); + break; +#if !IS_ENABLED(CONFIG_SPL_BUILD) || CONFIG_IS_ENABLED(MMC_SUPPORT) + case HCLK_SDMMC: + case HCLK_EMMC: + rate = rk3368_mmc_get_clk(priv->cru, clk->id); + break; +#endif + default: + return -ENOENT; + } + + return rate; +} + static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate) { __maybe_unused struct rk3368_clk_priv *priv = dev_get_priv(clk->dev); @@ -358,6 +435,9 @@ static ulong rk3368_clk_set_rate(struct clk *clk, ulong rate)
debug("%s id:%ld rate:%ld\n", __func__, clk->id, rate); switch (clk->id) { + case SCLK_SPI0 ... SCLK_SPI2: + ret = rk3368_spi_set_clk(priv->cru, clk->id, rate); + break; #if IS_ENABLED(CONFIG_TPL_BUILD) case CLK_DDR: ret = rk3368_ddr_set_clk(priv->cru, rate);