[U-Boot] [PATCH V2 07/14] imx: mx6: add clock api for lcdif

Peng Fan
2015-10-20T11:39:37Z

Implement mxs_set_lcdclk, enable_lcdif_clock and enable_pll_video.
The three API can be used to configure lcdif related clock when
CONFIG_VIDEO_MXS enabled.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
---

V2:
none

arch/arm/cpu/armv7/mx6/clock.c | 239 ++++++++++++++++++++++++++++++++++
arch/arm/include/asm/arch-mx6/clock.h | 2 +
2 files changed, 241 insertions(+)

diff --git a/arch/arm/cpu/armv7/mx6/clock.c b/arch/arm/cpu/armv7/mx6/clock.c
index 11efd12..8a88378 100644
--- a/arch/arm/cpu/armv7/mx6/clock.c
+++ b/arch/arm/cpu/armv7/mx6/clock.c
@@ -473,6 +473,245 @@ static u32 get_mmdc_ch0_clk(void)
}
}

+#if defined(CONFIG_VIDEO_MXS)
+static int enable_pll_video(u32 pll_div, u32 pll_num, u32 pll_denom,
+ u32 post_div)
+{
+ u32 reg = 0;
+ ulong start;
+
+ debug("pll5 div = %d, num = %d, denom = %d\n",
+ pll_div, pll_num, pll_denom);
+
+ /* Power up PLL5 video */
+ writel(BM_ANADIG_PLL_VIDEO_POWERDOWN |
+ BM_ANADIG_PLL_VIDEO_BYPASS |
+ BM_ANADIG_PLL_VIDEO_DIV_SELECT |
+ BM_ANADIG_PLL_VIDEO_POST_DIV_SELECT,
+ &imx_ccm->analog_pll_video_clr);
+
+ /* Set div, num and denom */
+ switch (post_div) {
+ case 1:
+ writel(BF_ANADIG_PLL_VIDEO_DIV_SELECT(pll_div) |
+ BF_ANADIG_PLL_VIDEO_POST_DIV_SELECT(0x2),
+ &imx_ccm->analog_pll_video_set);
+ break;
+ case 2:
+ writel(BF_ANADIG_PLL_VIDEO_DIV_SELECT(pll_div) |
+ BF_ANADIG_PLL_VIDEO_POST_DIV_SELECT(0x1),
+ &imx_ccm->analog_pll_video_set);
+ break;
+ case 4:
+ writel(BF_ANADIG_PLL_VIDEO_DIV_SELECT(pll_div) |
+ BF_ANADIG_PLL_VIDEO_POST_DIV_SELECT(0x0),
+ &imx_ccm->analog_pll_video_set);
+ break;
+ default:
+ puts("Wrong test_div!\n");
+ return -EINVAL;
+ }
+
+ writel(BF_ANADIG_PLL_VIDEO_NUM_A(pll_num),
+ &imx_ccm->analog_pll_video_num);
+ writel(BF_ANADIG_PLL_VIDEO_DENOM_B(pll_denom),
+ &imx_ccm->analog_pll_video_denom);
+
+ /* Wait PLL5 lock */
+ start = get_timer(0); /* Get current timestamp */
+
+ do {
+ reg = readl(&imx_ccm->analog_pll_video);
+ if (reg & BM_ANADIG_PLL_VIDEO_LOCK) {
+ /* Enable PLL out */
+ writel(BM_ANADIG_PLL_VIDEO_ENABLE,
+ &imx_ccm->analog_pll_video_set);
+ return 0;
+ }
+ } while (get_timer(0) < (start + 10)); /* Wait 10ms */
+
+ printf("Lock PLL5 timeout\n");
+
+ return -ETIME;
+}
+
+/*
+ * 24M--> PLL_VIDEO -> LCDIFx_PRED -> LCDIFx_PODF -> LCD
+ *
+ * 'freq' using KHz as unit, see driver/video/mxsfb.c.
+ */
+void mxs_set_lcdclk(u32 base_addr, u32 freq)
+{
+ u32 reg = 0;
+ u32 hck = MXC_HCLK / 1000;
+ /* DIV_SELECT ranges from 27 to 54 */
+ u32 min = hck * 27;
+ u32 max = hck * 54;
+ u32 temp, best = 0;
+ u32 i, j, max_pred = 8, max_postd = 8, pred = 1, postd = 1;
+ u32 pll_div, pll_num, pll_denom, post_div = 1;
+
+ debug("mxs_set_lcdclk, freq = %dKHz\n", freq);
+
+ if ((!is_cpu_type(MXC_CPU_MX6SX)) && !is_cpu_type(MXC_CPU_MX6UL))
+ return;
+
+ if (base_addr == LCDIF1_BASE_ADDR) {
+ reg = readl(&imx_ccm->cscdr2);
+ /* Can't change clocks when clock not from pre-mux */
+ if ((reg & MXC_CCM_CSCDR2_LCDIF1_CLK_SEL_MASK) != 0)
+ return;
+ }
+
+ if (is_cpu_type(MXC_CPU_MX6SX)) {
+ reg = readl(&imx_ccm->cscdr2);
+ /* Can't change clocks when clock not from pre-mux */
+ if ((reg & MXC_CCM_CSCDR2_LCDIF2_CLK_SEL_MASK) != 0)
+ return;
+ }
+
+ temp = freq * max_pred * max_postd;
+ if (temp > max) {
+ puts("Please decrease freq, too large!\n");
+ return;
+ }
+ if (temp < min) {
+ /*
+ * Register: PLL_VIDEO
+ * Bit Field: POST_DIV_SELECT
+ * 00 ??? Divide by 4.
+ * 01 ??? Divide by 2.
+ * 10 ??? Divide by 1.
+ * 11 ??? Reserved
+ * No need to check post_div(1)
+ */
+ for (post_div = 2; post_div <= 4; post_div <<= 1) {
+ if ((temp * post_div) > min) {
+ freq *= post_div;
+ break;
+ }
+ }
+
+ if (post_div > 4) {
+ printf("Fail to set rate to %dkhz", freq);
+ return;
+ }
+ }
+
+ /* Choose the best pred and postd to match freq for lcd */
+ for (i = 1; i <= max_pred; i++) {
+ for (j = 1; j <= max_postd; j++) {
+ temp = freq * i * j;
+ if (temp > max || temp < min)
+ continue;
+ if (best == 0 || temp < best) {
+ best = temp;
+ pred = i;
+ postd = j;
+ }
+ }
+ }
+
+ if (best == 0) {
+ printf("Fail to set rate to %dKHz", freq);
+ return;
+ }
+
+ debug("best %d, pred = %d, postd = %d\n", best, pred, postd);
+
+ pll_div = best / hck;
+ pll_denom = 1000000;
+ pll_num = (best - hck * pll_div) * pll_denom / hck;
+
+ /*
+ * pll_num
+ * (24MHz * (pll_div + --------- ))
+ * pll_denom
+ *freq KHz = --------------------------------
+ * post_div * pred * postd * 1000
+ */
+
+ if (base_addr == LCDIF1_BASE_ADDR) {
+ if (enable_pll_video(pll_div, pll_num, pll_denom, post_div))
+ return;
+
+ /* Select pre-lcd clock to PLL5 and set pre divider */
+ clrsetbits_le32(&imx_ccm->cscdr2,
+ MXC_CCM_CSCDR2_LCDIF1_PRED_SEL_MASK |
+ MXC_CCM_CSCDR2_LCDIF1_PRE_DIV_MASK,
+ (0x2 << MXC_CCM_CSCDR2_LCDIF1_PRED_SEL_OFFSET) |
+ ((pred - 1) <<
+ MXC_CCM_CSCDR2_LCDIF1_PRE_DIV_OFFSET));
+
+ /* Set the post divider */
+ clrsetbits_le32(&imx_ccm->cbcmr,
+ MXC_CCM_CBCMR_LCDIF1_PODF_MASK,
+ ((postd - 1) <<
+ MXC_CCM_CBCMR_LCDIF1_PODF_OFFSET));
+ }
+
+ if (is_cpu_type(MXC_CPU_MX6SX)) {
+ if (enable_pll_video(pll_div, pll_num, pll_denom, post_div))
+ return;
+
+ /* Select pre-lcd clock to PLL5 and set pre divider */
+ clrsetbits_le32(&imx_ccm->cscdr2,
+ MXC_CCM_CSCDR2_LCDIF2_PRED_SEL_MASK |
+ MXC_CCM_CSCDR2_LCDIF2_PRE_DIV_MASK,
+ (0x2 << MXC_CCM_CSCDR2_LCDIF2_PRED_SEL_OFFSET) |
+ ((pred - 1) <<
+ MXC_CCM_CSCDR2_LCDIF2_PRE_DIV_OFFSET));
+
+ /* Set the post divider */
+ clrsetbits_le32(&imx_ccm->cscmr1,
+ MXC_CCM_CSCMR1_LCDIF2_PODF_MASK,
+ ((postd - 1) <<
+ MXC_CCM_CSCMR1_LCDIF2_PODF_OFFSET));
+ }
+}
+
+void enable_lcdif_clock(u32 index)
+{
+ u32 reg = 0;
+ u32 lcdif_clk_sel_mask, lcdif_ccgr3_mask;
+
+ if (is_cpu_type(MXC_CPU_MX6SX)) {
+ if (index > 1)
+ return;
+ /* Set to pre-mux clock at default */
+ lcdif_clk_sel_mask = (index == 1) ?
+ MXC_CCM_CSCDR2_LCDIF2_CLK_SEL_MASK :
+ MXC_CCM_CSCDR2_LCDIF1_CLK_SEL_MASK;
+ lcdif_ccgr3_mask = (index == 1) ?
+ (MXC_CCM_CCGR3_LCDIF2_PIX_MASK |
+ MXC_CCM_CCGR3_DISP_AXI_MASK) :
+ (MXC_CCM_CCGR3_LCDIF1_PIX_MASK |
+ MXC_CCM_CCGR3_DISP_AXI_MASK);
+ } else if (is_cpu_type(MXC_CPU_MX6UL)) {
+ if (index > 0)
+ return;
+ /* Set to pre-mux clock at default */
+ lcdif_clk_sel_mask = MXC_CCM_CSCDR2_LCDIF1_CLK_SEL_MASK;
+ lcdif_ccgr3_mask = MXC_CCM_CCGR3_LCDIF1_PIX_MASK;
+ } else {
+ return;
+ }
+
+ reg = readl(&imx_ccm->cscdr2);
+ reg &= ~lcdif_clk_sel_mask;
+ writel(reg, &imx_ccm->cscdr2);
+
+ /* Enable the LCDIF pix clock */
+ reg = readl(&imx_ccm->CCGR3);
+ reg |= lcdif_ccgr3_mask;
+ writel(reg, &imx_ccm->CCGR3);
+
+ reg = readl(&imx_ccm->CCGR2);
+ reg |= MXC_CCM_CCGR2_LCD_MASK;
+ writel(reg, &imx_ccm->CCGR2);
+}
+#endif
+
#ifdef CONFIG_FSL_QSPI
/* qspi_num can be from 0 - 1 */
void enable_qspi_clk(int qspi_num)
diff --git a/arch/arm/include/asm/arch-mx6/clock.h b/arch/arm/include/asm/arch-mx6/clock.h
index 2b220d6..15d14f0 100644
--- a/arch/arm/include/asm/arch-mx6/clock.h
+++ b/arch/arm/include/asm/arch-mx6/clock.h
@@ -66,6 +66,8 @@ int enable_spi_clk(unsigned char enable, unsigned spi_num);
void enable_ipu_clock(void);
int enable_fec_anatop_clock(int fec_id, enum enet_freq freq);
void enable_enet_clk(unsigned char enable);
+void enable_lcdif_clock(unsigned int index);
void enable_qspi_clk(int qspi_num);
void enable_thermal_clk(void);
+void mxs_set_lcdclk(u32 base_addr, u32 freq);
#endif /* __ASM_ARCH_CLOCK_H */
--
1.8.4