drivers: marvell: add thermal sensor driver and expose it via SIP service

Since the dfx register set is going to be marked as secure (in order to
protect efuse registers for non secure access), accessing thermal
registers which are part of dfx register set, will not be possible from
lower exception levels. Due to above expose thermal driver as a SiP
service.  This will allow Linux and U-Boot thermal driver to initialise
and perform various operations on thermal sensor.

The thermal sensor driver is based on Linux
drivers/thermal/armada_thermal.c.

Change-Id: I4763a3bf5c43750c724c86b1dcadad3cb729e93e
Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Reviewed-on: https://sj1git1.cavium.com/20581

Reviewed-by: Kostya Porotchkin <kostap@marvell.com>
Tested-by: Kostya Porotchkin <kostap@marvell.com>

drivers/marvell/secure_dfx_access/armada_thermal.c

+/*
+ * Copyright (C) 2019 Marvell International Ltd.
+ *
+ * SPDX-License-Identifier:     BSD-3-Clause
+ * https://spdx.org/licenses
+ */
+#include <common/debug.h>
+#include <drivers/delay_timer.h>
+#include <errno.h>
+#include <lib/mmio.h>
+#include <mvebu.h>
+#include <stdbool.h>
+#include "dfx.h"
+
+/* #define DEBUG_DFX */
+#ifdef DEBUG_DFX
+#define debug(format...) NOTICE(format)
+#else
+#define debug(format, arg...)
+#endif
+
+#define TSEN_CTRL0			0xf06f8084
+ #define TSEN_CTRL0_START		BIT(0)
+ #define TSEN_CTRL0_RESET		BIT(1)
+ #define TSEN_CTRL0_ENABLE		BIT(2)
+ #define TSEN_CTRL0_AVG_BYPASS		BIT(6)
+ #define TSEN_CTRL0_CHAN_SHIFT		13
+ #define TSEN_CTRL0_CHAN_MASK		0xF
+ #define TSEN_CTRL0_OSR_SHIFT		24
+ #define TSEN_CTRL0_OSR_MAX		0x3
+ #define TSEN_CTRL0_MODE_SHIFT		30
+ #define TSEN_CTRL0_MODE_EXTERNAL	0x2U
+ #define TSEN_CTRL0_MODE_MASK		0x3U
+
+#define TSEN_CTRL1			0xf06f8088
+ #define TSEN_CTRL1_INT_EN		BIT(25)
+ #define TSEN_CTRL1_HYST_SHIFT		19
+ #define TSEN_CTRL1_HYST_MASK		(0x3 << TSEN_CTRL1_HYST_SHIFT)
+ #define TSEN_CTRL1_THRESH_SHIFT	3
+ #define TSEN_CTRL1_THRESH_MASK		(0x3ff << TSEN_CTRL1_THRESH_SHIFT)
+
+#define TSEN_STATUS			0xf06f808c
+ #define TSEN_STATUS_VALID_OFFSET	16
+ #define TSEN_STATUS_VALID_MASK		(0x1 << TSEN_STATUS_VALID_OFFSET)
+ #define TSEN_STATUS_TEMP_OUT_OFFSET	0
+ #define TSEN_STATUS_TEMP_OUT_MASK	(0x3FF << TSEN_STATUS_TEMP_OUT_OFFSET)
+
+#define DFX_SERVER_IRQ_SUM_MASK_REG	0xf06f8104
+ #define DFX_SERVER_IRQ_EN		BIT(1)
+
+#define DFX_IRQ_CAUSE_REG		0xf06f8108
+
+#define DFX_IRQ_MASK_REG		0xf06f810c
+ #define DFX_IRQ_TSEN_OVERHEAT_OFFSET	BIT(22)
+
+#define THERMAL_SEN_OUTPUT_MSB		512
+#define THERMAL_SEN_OUTPUT_COMP		1024
+
+#define COEF_M 423
+#define COEF_B -150000LL
+
+static void armada_ap806_thermal_read(u_register_t *temp)
+{
+	uint32_t reg;
+
+	reg = mmio_read_32(TSEN_STATUS);
+
+	reg = ((reg & TSEN_STATUS_TEMP_OUT_MASK) >>
+	      TSEN_STATUS_TEMP_OUT_OFFSET);
+
+	/*
+	 * TSEN output format is signed as a 2s complement number
+	 * ranging from-512 to +511. when MSB is set, need to
+	 * calculate the complement number
+	 */
+	if (reg >= THERMAL_SEN_OUTPUT_MSB)
+		reg -= THERMAL_SEN_OUTPUT_COMP;
+
+	*temp = ((COEF_M * ((signed int)reg)) - COEF_B);
+}
+
+static void armada_ap806_thermal_irq(void)
+{
+	/* Dummy read, register ROC */
+	mmio_read_32(DFX_IRQ_CAUSE_REG);
+}
+
+static void armada_ap806_thermal_overheat_irq_init(void)
+{
+	uint32_t reg;
+
+	/* Clear DFX temperature IRQ cause */
+	reg = mmio_read_32(DFX_IRQ_CAUSE_REG);
+
+	/* Enable DFX Temperature IRQ */
+	reg = mmio_read_32(DFX_IRQ_MASK_REG);
+	reg |= DFX_IRQ_TSEN_OVERHEAT_OFFSET;
+	mmio_write_32(DFX_IRQ_MASK_REG, reg);
+
+	/* Enable DFX server IRQ */
+	reg = mmio_read_32(DFX_SERVER_IRQ_SUM_MASK_REG);
+	reg |= DFX_SERVER_IRQ_EN;
+	mmio_write_32(DFX_SERVER_IRQ_SUM_MASK_REG, reg);
+
+	/* Enable overheat interrupt */
+	reg = mmio_read_32(TSEN_CTRL1);
+	reg |= TSEN_CTRL1_INT_EN;
+	mmio_write_32(TSEN_CTRL1, reg);
+}
+
+static unsigned int armada_mc_to_reg_temp(unsigned int temp_mc)
+{
+	unsigned int sample;
+
+	sample = (temp_mc + COEF_B) / COEF_M;
+
+	return sample & 0x3ff;
+}
+
+/*
+ * The documentation states:
+ * high/low watermark = threshold +/- 0.4761 * 2^(hysteresis + 2)
+ * which is the mathematical derivation for:
+ * 0x0 <=> 1.9°C, 0x1 <=> 3.8°C, 0x2 <=> 7.6°C, 0x3 <=> 15.2°C
+ */
+static unsigned int hyst_levels_mc[] = {1900, 3800, 7600, 15200};
+
+static unsigned int armada_mc_to_reg_hyst(int hyst_mc)
+{
+	int i;
+
+	/*
+	 * We will always take the smallest possible hysteresis to avoid risking
+	 * the hardware integrity by enlarging the threshold by +8°C in the
+	 * worst case.
+	 */
+	for (i = ARRAY_SIZE(hyst_levels_mc) - 1; i > 0; i--)
+		if (hyst_mc >= hyst_levels_mc[i])
+			break;
+
+	return i;
+}
+
+static void armada_ap806_thermal_threshold(int thresh_mc, int hyst_mc)
+{
+	uint32_t ctrl1;
+	unsigned int threshold = armada_mc_to_reg_temp(thresh_mc);
+	unsigned int hysteresis = armada_mc_to_reg_hyst(hyst_mc);
+
+	ctrl1 = mmio_read_32(TSEN_CTRL1);
+	/* Set Threshold */
+	if (thresh_mc >= 0) {
+		ctrl1 &= ~(TSEN_CTRL1_THRESH_MASK);
+		ctrl1 |= threshold << TSEN_CTRL1_THRESH_SHIFT;
+	}
+
+	/* Set Hysteresis */
+	if (hyst_mc >= 0) {
+		ctrl1 &= ~(TSEN_CTRL1_HYST_MASK);
+		ctrl1 |= hysteresis << TSEN_CTRL1_HYST_SHIFT;
+	}
+
+	mmio_write_32(TSEN_CTRL1, ctrl1);
+}
+
+static void armada_select_channel(int channel)
+{
+	uint32_t ctrl0;
+
+	/* Stop the measurements */
+	ctrl0 = mmio_read_32(TSEN_CTRL0);
+	ctrl0 &= ~TSEN_CTRL0_START;
+	mmio_write_32(TSEN_CTRL0, ctrl0);
+
+	/* Reset the mode, internal sensor will be automatically selected */
+	ctrl0 &= ~(TSEN_CTRL0_MODE_MASK << TSEN_CTRL0_MODE_SHIFT);
+
+	/* Other channels are external and should be selected accordingly */
+	if (channel) {
+		/* Change the mode to external */
+		ctrl0 |= TSEN_CTRL0_MODE_EXTERNAL <<
+			 TSEN_CTRL0_MODE_SHIFT;
+		/* Select the sensor */
+		ctrl0 &= ~(TSEN_CTRL0_CHAN_MASK << TSEN_CTRL0_CHAN_SHIFT);
+		ctrl0 |= (channel - 1) << TSEN_CTRL0_CHAN_SHIFT;
+	}
+
+	/* Actually set the mode/channel */
+	mmio_write_32(TSEN_CTRL0, ctrl0);
+
+	/* Re-start the measurements */
+	ctrl0 |= TSEN_CTRL0_START;
+	mmio_write_32(TSEN_CTRL0, ctrl0);
+}
+
+static void armada_ap806_thermal_init(void)
+{
+	uint32_t reg;
+
+	reg = mmio_read_32(TSEN_CTRL0);
+	reg &= ~TSEN_CTRL0_RESET;
+	reg |= TSEN_CTRL0_START | TSEN_CTRL0_ENABLE;
+
+	/* Sample every ~2ms */
+	reg |= TSEN_CTRL0_OSR_MAX << TSEN_CTRL0_OSR_SHIFT;
+
+	/* Enable average (2 samples by default) */
+	reg &= ~TSEN_CTRL0_AVG_BYPASS;
+
+	mmio_write_32(TSEN_CTRL0, reg);
+
+	debug("thermal: Initialization done\n");
+}
+
+static void armada_is_valid(u_register_t *read)
+{
+	*read = (mmio_read_32(TSEN_STATUS) & TSEN_STATUS_VALID_MASK);
+}
+
+int mvebu_dfx_handle(u_register_t func, u_register_t *read, u_register_t x2,
+		     u_register_t x3)
+{
+	debug_enter();
+
+	switch (func) {
+	case MV_SIP_DFX_THERMAL_INIT:
+		armada_ap806_thermal_init();
+		break;
+	case MV_SIP_DFX_THERMAL_READ:
+		armada_ap806_thermal_read(read);
+		break;
+	case MV_SIP_DFX_THERMAL_IRQ:
+		armada_ap806_thermal_irq();
+		break;
+	case MV_SIP_DFX_THERMAL_THRESH:
+		armada_ap806_thermal_threshold(x2, x3);
+		armada_ap806_thermal_overheat_irq_init();
+		break;
+	case MV_SIP_DFX_THERMAL_IS_VALID:
+		armada_is_valid(read);
+		break;
+	case MV_SIP_DFX_THERMAL_SEL_CHANNEL:
+		armada_select_channel(x2);
+		break;
+	default:
+		ERROR("unsupported dfx func\n");
+		return -EINVAL;
+	}
+
+	debug_exit();
+
+	return 0;
+}

drivers/marvell/secure_dfx_access/dfx.h

+/*
+ * Copyright (C) 2019 Marvell International Ltd.
+ *
+ * SPDX-License-Identifier:     BSD-3-Clause
+ * https://spdx.org/licenses
+ */
+
+/* DFX sub-FID */
+#define MV_SIP_DFX_THERMAL_INIT		1
+#define MV_SIP_DFX_THERMAL_READ		2
+#define MV_SIP_DFX_THERMAL_IS_VALID	3
+#define MV_SIP_DFX_THERMAL_IRQ		4
+#define MV_SIP_DFX_THERMAL_THRESH	5
+#define MV_SIP_DFX_THERMAL_SEL_CHANNEL	6
+
+int mvebu_dfx_handle(u_register_t func, u_register_t *read, u_register_t x2,
+		     u_register_t x3);

plat/marvell/armada/a8k/common/a8k_common.mk

@@ -115,6 +115,7 @@ MARVELL_DRV		:= 	$(MARVELL_DRV_BASE)/io_win.c	\
 				$(MARVELL_DRV_BASE)/comphy/phy-comphy-cp110.c	\
 				$(MARVELL_DRV_BASE)/mc_trustzone/mc_trustzone.c	\
 				$(MARVELL_DRV_BASE)/mg_conf_cm3/mg_conf_cm3.c	\
+				$(MARVELL_DRV_BASE)/secure_dfx_access/armada_thermal.c \
 				drivers/rambus/trng_ip_76.c
 
 BL31_PORTING_SOURCES	:=	$(BOARD_DIR)/board/marvell_plat_config.c

plat/marvell/armada/common/mrvl_sip_svc.c

@@ -16,6 +16,7 @@
 #include <plat_marvell.h>
 
 #include "comphy/phy-comphy-cp110.h"
+#include "secure_dfx_access/dfx.h"
 #include <stdbool.h>
 
 /* #define DEBUG_COMPHY */
@@ -37,6 +38,7 @@
 #define MV_SIP_LLC_ENABLE	0x82000011
 #define MV_SIP_PMU_IRQ_ENABLE	0x82000012
 #define MV_SIP_PMU_IRQ_DISABLE	0x82000013
+#define MV_SIP_DFX		0x82000014
 
 /* TRNG */
 #define MV_SIP_RNG_64		0xC200FF11
@@ -71,7 +73,7 @@ uintptr_t mrvl_sip_smc_handler(uint32_t smc_fid,
 			       void *handle,
 			       u_register_t flags)
 {
-	u_register_t ret;
+	u_register_t ret, read;
 	uint32_t w2[2] = {0, 0};
 	int i;
 
@@ -136,6 +138,9 @@ uintptr_t mrvl_sip_smc_handler(uint32_t smc_fid,
 		mvebu_pmu_interrupt_disable();
 		SMC_RET1(handle, 0);
 #endif
+	case MV_SIP_DFX:
+		ret = mvebu_dfx_handle(x1, &read, x2, x3);
+		SMC_RET2(handle, ret, read);
 	case MV_SIP_RNG_64:
 		ret = eip76_rng_get_random((uint8_t *)&w2, 4 * (x1 % 2 + 1));
 		SMC_RET3(handle, ret, w2[0], w2[1]);