soc/qualcomm/common: clock: Add support for common clock driver

The clock driver supports configuring the general purpose PLLs,
configuring the root clock generator (RCG), enable clock branch, enable
gdsc and also the block resets.

The common clock driver exposes PLL configuration functions and also
different Agera PLL enable functions for the CPU PLLs.

While at it, the common driver also supports reset of subsystems like
AOP and SHRM.

SC7180 clock driver is also refactored to use the common clock
driver APIs.

BUG=b:182963902
TEST=Validated on qualcomm sc7180 and sc7280 development board.

Change-Id: I03d1b4a2fb90303c7259ec08f312d78b4e33ec39
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56588
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Shelley Chen <shchen@google.com>
diff --git a/src/soc/qualcomm/common/clock.c b/src/soc/qualcomm/common/clock.c
new file mode 100644
index 0000000..e83f979
--- /dev/null
+++ b/src/soc/qualcomm/common/clock.c
@@ -0,0 +1,243 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <assert.h>
+#include <commonlib/helpers.h>
+#include <delay.h>
+#include <device/mmio.h>
+#include <soc/clock.h>
+#include <timer.h>
+#include <types.h>
+
+/* Clock Branch Operations */
+static bool clock_is_off(u32 *cbcr_addr)
+{
+	return (read32(cbcr_addr) & CLK_CTL_OFF_BMSK);
+}
+
+enum cb_err clock_enable_vote(void *cbcr_addr, void *vote_addr,
+				uint32_t vote_bit)
+{
+	int count = 100;
+
+	setbits32(vote_addr, BIT(vote_bit));
+
+	/* Ensure clock is enabled */
+	while (count-- > 0) {
+		if (!clock_is_off(cbcr_addr))
+			return CB_SUCCESS;
+		udelay(1);
+	}
+	printk(BIOS_ERR, "ERROR: Failed to enable clock, register val: 0x%x\n",
+			read32(cbcr_addr));
+	return CB_ERR;
+}
+
+enum cb_err clock_enable(void *cbcr_addr)
+{
+	int count = 100;
+
+	/* Set clock enable bit */
+	setbits32(cbcr_addr, BIT(CLK_CTL_EN_SHFT));
+
+	/* Ensure clock is enabled */
+	while (count-- > 0) {
+		if (!clock_is_off(cbcr_addr))
+			return CB_SUCCESS;
+		udelay(1);
+	}
+	printk(BIOS_ERR, "ERROR: Failed to enable clock, register val: 0x%x\n",
+			read32(cbcr_addr));
+	return CB_ERR;
+}
+
+/* Clock Block Reset Operations */
+void clock_reset_bcr(void *bcr_addr, bool assert)
+{
+	if (assert)
+		setbits32(bcr_addr, BIT(CLK_CTL_BCR_BLK_SHFT));
+	else
+		clrbits32(bcr_addr, BIT(CLK_CTL_BCR_BLK_SHFT));
+}
+
+/* Clock GDSC Operations */
+enum cb_err enable_and_poll_gdsc_status(void *gdscr_addr)
+{
+	if (read32(gdscr_addr) & CLK_CTL_OFF_BMSK)
+		return CB_SUCCESS;
+
+	clrbits32(gdscr_addr, BIT(GDSC_ENABLE_BIT));
+
+	/* Ensure gdsc is enabled */
+	if (!wait_us(100, (read32(gdscr_addr) & CLK_CTL_OFF_BMSK)))
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/* Clock Root clock Generator with MND Operations */
+static void clock_configure_mnd(struct clock_rcg *clk, uint32_t m, uint32_t n,
+				uint32_t d_2)
+{
+	struct clock_rcg_mnd *mnd = (struct clock_rcg_mnd *)clk;
+
+	setbits32(&clk->rcg_cfg,
+			RCG_MODE_DUAL_EDGE << CLK_CTL_CFG_MODE_SHFT);
+
+	write32(&mnd->m, m & CLK_CTL_RCG_MND_BMSK);
+	write32(&mnd->n, ~(n-m) & CLK_CTL_RCG_MND_BMSK);
+	write32(&mnd->d_2, ~(d_2) & CLK_CTL_RCG_MND_BMSK);
+}
+
+/* Clock Root clock Generator Operations */
+enum cb_err clock_configure(struct clock_rcg *clk,
+			struct clock_freq_config *clk_cfg, uint32_t hz,
+			uint32_t num_perfs)
+{
+	uint32_t reg_val, idx;
+
+	for (idx = 0; idx < num_perfs; idx++)
+		if (hz <= clk_cfg[idx].hz)
+			break;
+
+	reg_val = (clk_cfg[idx].src << CLK_CTL_CFG_SRC_SEL_SHFT) |
+			(clk_cfg[idx].div << CLK_CTL_CFG_SRC_DIV_SHFT);
+
+	/* Set clock config */
+	write32(&clk->rcg_cfg, reg_val);
+
+	if (clk_cfg[idx].m != 0)
+		clock_configure_mnd(clk, clk_cfg[idx].m, clk_cfg[idx].n,
+				clk_cfg[idx].d_2);
+
+	/* Commit config to RCG */
+	setbits32(&clk->rcg_cmd, BIT(CLK_CTL_CMD_UPDATE_SHFT));
+
+	return CB_SUCCESS;
+}
+
+/* Clock Root clock Generator with DFS Operations */
+void clock_configure_dfsr_table(int qup, struct clock_freq_config *clk_cfg,
+		uint32_t num_perfs)
+{
+	struct qupv3_clock *qup_clk;
+	unsigned int idx, s = qup % QUP_WRAP1_S0;
+	uint32_t reg_val;
+
+	qup_clk = qup < QUP_WRAP1_S0 ?
+				&gcc->qup_wrap0_s[s] : &gcc->qup_wrap1_s[s];
+
+	clrsetbits32(&qup_clk->dfsr_clk.cmd_dfsr,
+			BIT(CLK_CTL_CMD_RCG_SW_CTL_SHFT),
+			BIT(CLK_CTL_CMD_DFSR_SHFT));
+
+	for (idx = 0; idx < num_perfs; idx++) {
+		reg_val = (clk_cfg[idx].src << CLK_CTL_CFG_SRC_SEL_SHFT) |
+			(clk_cfg[idx].div << CLK_CTL_CFG_SRC_DIV_SHFT);
+
+		write32(&qup_clk->dfsr_clk.perf_dfsr[idx], reg_val);
+
+		if (clk_cfg[idx].m == 0)
+			continue;
+
+		setbits32(&qup_clk->dfsr_clk.perf_dfsr[idx],
+				RCG_MODE_DUAL_EDGE << CLK_CTL_CFG_MODE_SHFT);
+
+		reg_val = clk_cfg[idx].m & CLK_CTL_RCG_MND_BMSK;
+		write32(&qup_clk->dfsr_clk.perf_m_dfsr[idx], reg_val);
+
+		reg_val = ~(clk_cfg[idx].n - clk_cfg[idx].m)
+				& CLK_CTL_RCG_MND_BMSK;
+		write32(&qup_clk->dfsr_clk.perf_n_dfsr[idx], reg_val);
+
+		reg_val = ~(clk_cfg[idx].d_2) & CLK_CTL_RCG_MND_BMSK;
+		write32(&qup_clk->dfsr_clk.perf_d_dfsr[idx], reg_val);
+	}
+}
+
+/* General Purpose PLL configuration and enable Operations */
+enum cb_err clock_configure_enable_gpll(struct alpha_pll_reg_val_config *cfg,
+					bool enable, int br_enable)
+{
+	if (cfg->l_val)
+		write32(cfg->reg_l, cfg->l_val);
+
+	if (cfg->cal_l_val)
+		write32(cfg->reg_cal_l, cfg->cal_l_val);
+
+	if (cfg->alpha_val)
+		write32(cfg->reg_alpha, cfg->alpha_val);
+
+	if (cfg->user_ctl_val)
+		write32(cfg->reg_user_ctl, cfg->user_ctl_val);
+
+	if (cfg->user_ctl_hi_val)
+		write32(cfg->reg_user_ctl_hi, cfg->user_ctl_hi_val);
+
+	if (cfg->user_ctl_hi1_val)
+		write32(cfg->reg_user_ctl_hi1, cfg->user_ctl_hi1_val);
+
+	if (cfg->config_ctl_val)
+		write32(cfg->reg_config_ctl, cfg->config_ctl_val);
+
+	if (cfg->config_ctl_hi_val)
+		write32(cfg->reg_config_ctl_hi, cfg->config_ctl_hi_val);
+
+	if (cfg->config_ctl_hi1_val)
+		write32(cfg->reg_config_ctl_hi1, cfg->config_ctl_hi1_val);
+
+	if (cfg->fsm_enable)
+		setbits32(cfg->reg_mode, BIT(PLL_FSM_EN_SHFT));
+
+	if (enable) {
+		setbits32(cfg->reg_opmode, BIT(PLL_STANDBY_MODE));
+
+		/*
+		* H/W requires a 1us delay between placing PLL in STANDBY and
+		* de-asserting the reset.
+		*/
+		udelay(1);
+		setbits32(cfg->reg_mode, BIT(PLL_RESET_N_SHFT));
+
+		/*
+		* H/W requires a 10us delay between de-asserting the reset and
+		* enabling the PLL branch bit.
+		*/
+		udelay(10);
+		setbits32(cfg->reg_apcs_pll_br_en, BIT(br_enable));
+
+		/* Wait for Lock Detection */
+		if (!wait_us(100, read32(cfg->reg_mode) & PLL_LOCK_DET_BMSK)) {
+			printk(BIOS_ERR, "ERROR: PLL did not lock!\n");
+			return CB_ERR;
+		}
+	}
+
+	return CB_SUCCESS;
+}
+
+enum cb_err agera_pll_enable(struct alpha_pll_reg_val_config *cfg)
+{
+	setbits32(cfg->reg_mode, BIT(PLL_BYPASSNL_SHFT));
+
+	/*
+	* H/W requires a 5us delay between disabling the bypass and
+	* de-asserting the reset.
+	*/
+	udelay(5);
+	setbits32(cfg->reg_mode, BIT(PLL_RESET_SHFT));
+
+	if (!wait_us(100, read32(cfg->reg_mode) & PLL_LOCK_DET_BMSK)) {
+		printk(BIOS_ERR, "ERROR: CPU PLL did not lock!\n");
+		return CB_ERR;
+	}
+
+	setbits32(cfg->reg_mode, BIT(PLL_OUTCTRL_SHFT));
+
+	return CB_SUCCESS;
+}
+
+/* Bring subsystem out of RESET */
+void clock_reset_subsystem(u32 *misc, u32 shft)
+{
+	clrbits32(misc, BIT(shft));
+}