zynqmp: pm: Reimplement clock disable EEMI API

Clock disable EEMI API is reimplemented to use system-level clock
and pll EEMI APIs rather than direct MMIO read/write accesses to clock
and pll control registers.
Since linux still uses clock disable API to reset the PLL in the
implementation of pm_clock_disable() we need to workaround this by
distinguishing two cases: 1) if the given clock ID corresponds to a PLL
output clock ID; or 2) given clock ID is truly an on-chip clock that can
be gated.
For case 1) we'll call pm_api_clock_pll_disable() implemented in
pm_api_clock.h/c. This function will reset the PLL using the system-level
PLL set mode EEMI API with the reset mode argument.
For case 2) we'll call the PMU to configure the clock gate. This is done
using system-level clock disable EEMI API.
Functions that appear to be unused after this change is made are removed.

Signed-off-by: Mirela Simonovic <mirela.simonovic@aggios.com>
Acked-by: Will Wong <WILLW@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>

plat/xilinx/zynqmp/pm_service/pm_api_clock.c

@@ -2626,58 +2626,6 @@ pm_api_pll_bypass_and_reset(unsigned int clock_id, unsigned int flag)
 	return ret;
 }
 
-/**
- * pm_api_clk_enable_disable() - Enable/Disable the clock for given id
- * @clock_id: Id of the clock to be enabled
- * @enable: Enable(1)/Disable(0)
- *
- * This function is to enable/disable the clock which is not PLL.
- *
- * Return: Returns status, either success or error+reason.
- */
-static enum pm_ret_status pm_api_clk_enable_disable(unsigned int clock_id,
-						    unsigned int enable)
-{
-	enum pm_ret_status ret = PM_RET_SUCCESS;
-	struct pm_clock_node *nodes = *clocks[clock_id].nodes;
-	uint8_t num_nodes = clocks[clock_id].num_nodes;
-	unsigned int reg, val;
-	uint8_t i = 0;
-	uint8_t offset = NA_SHIFT, width = NA_WIDTH;
-
-	if (clock_id == CLK_GEM0_TX || clock_id == CLK_GEM1_TX ||
-	    clock_id == CLK_GEM2_TX || clock_id == CLK_GEM3_TX)
-		reg = clocks[clock_id].status_reg;
-	else
-		reg = clocks[clock_id].control_reg;
-
-	for (i = 0; i < num_nodes; i++) {
-		if (nodes->type == TYPE_GATE) {
-			offset = nodes->offset;
-			width = nodes->width;
-			break;
-		}
-		nodes++;
-	}
-	if (width == NA_WIDTH)
-		return PM_RET_ERROR_NOTSUPPORTED;
-
-	ret = pm_mmio_read(reg, &val);
-	if (ret != PM_RET_SUCCESS)
-		return ret;
-	if ((val & BIT_MASK(offset, width)) == enable)
-		return PM_RET_SUCCESS;
-
-	if (enable == 0)
-		val &= ~(BIT_MASK(offset, width));
-	else
-		val |= BIT_MASK(offset, width);
-
-	ret = pm_mmio_write(reg, BIT_MASK(offset, width), val);
-
-	return ret;
-}
-
 /**
  * pm_clock_pll_enable() - "Enable" the PLL clock (lock the PLL)
  * @pll: PLL to be locked
@@ -2700,33 +2648,20 @@ enum pm_ret_status pm_clock_pll_enable(struct pm_pll *pll)
 }
 
 /**
- * pm_api_clock_disable - Disable the clock for given id
- * @clock_id	Id of the clock to be disable
+ * pm_clock_pll_disable - "Disable" the PLL clock (bypass/reset the PLL)
+ * @pll		PLL to be bypassed/reset
  *
- * This function is used by master to disable the clock
- * including peripherals and PLL clocks.
+ * This function is used to map IOCTL/linux-based PLL handling to system-level
+ * EEMI APIs
  *
- * Return: Returns status, either success or error+reason.
+ * Return: Error if the argument is not valid or status as returned by PMU
  */
-
-enum pm_ret_status pm_api_clock_disable(unsigned int clock_id)
+enum pm_ret_status pm_clock_pll_disable(struct pm_pll *pll)
 {
-	enum pm_ret_status ret = PM_RET_SUCCESS;
-
-	if (!pm_clock_valid(clock_id))
+	if (!pll)
 		return PM_RET_ERROR_ARGS;
 
-	if (pm_clock_type(clock_id) != CLK_TYPE_OUTPUT)
-		return PM_RET_ERROR_NOTSUPPORTED;
-
-	/*
-	 * PLL type clock should not be disabled explicitly.
-	 * It is done by PMUFW if required.
-	 */
-	if (!ISPLL(clock_id))
-		ret = pm_api_clk_enable_disable(clock_id, 0);
-
-	return ret;
+	return pm_pll_set_mode(pll->nid, PM_PLL_MODE_RESET);
 }
 
 /**

plat/xilinx/zynqmp/pm_service/pm_api_clock.h

@@ -296,7 +296,7 @@ enum pm_ret_status pm_clock_get_pll_node_id(enum clock_id clock_id,
 enum pm_ret_status pm_clock_id_is_valid(unsigned int clock_id);
 
 enum pm_ret_status pm_clock_pll_enable(struct pm_pll *pll);
-enum pm_ret_status pm_api_clock_disable(unsigned int clock_id);
+enum pm_ret_status pm_clock_pll_disable(struct pm_pll *pll);
 enum pm_ret_status pm_api_clock_getstate(unsigned int clock_id,
 					 unsigned int *state);
 enum pm_ret_status pm_api_clock_setdivider(unsigned int clock_id,

plat/xilinx/zynqmp/pm_service/pm_api_sys.c

@@ -903,12 +903,20 @@ enum pm_ret_status pm_clock_enable(unsigned int clock_id)
  * This function is used by master to disable the clock
  * including peripherals and PLL clocks.
  *
- * Return: Returns status, either success or error+reason.
+ * @return:	Error if an argument is not valid or status as returned by the
+ *		pm_clock_gate
  */
-
 enum pm_ret_status pm_clock_disable(unsigned int clock_id)
 {
-	return pm_api_clock_disable(clock_id);
+	struct pm_pll *pll;
+
+	/* First try to handle it as a PLL */
+	pll = pm_clock_get_pll(clock_id);
+	if (pll)
+		return pm_clock_pll_disable(pll);
+
+	/* It's an on-chip clock, PMU should configure clock's gate */
+	return pm_clock_gate(clock_id, 0);
 }
 
 /**