driver: misc: k3_avs: Add support for thermal shutdown

To avoid thermal burn out, program thermal shutdown
value in VTM (Voltage and Thermal Manager) IP.

Part of Linux kernel driver (drivers/thermal/k3_j72xx_bandgap.c)
is ported from kernel 6.6-rc1, which sets thermal shutdown values.

Signed-off-by: Udit Kumar <u-kumar1@ti.com>
Signed-off-by: Neha Francis <n-francis@ti.com>

diff --git a/drivers/misc/k3_avs.c b/drivers/misc/k3_avs.c
index acfc73184520ca98341aa50b319ec460b4fa2687..9a088244dd1efdc50d002b297db6e282e44ce1a5 100644 (file)
--- a/drivers/misc/k3_avs.c
+++ b/drivers/misc/k3_avs.c
@@ -15,6 +15,7 @@
 #include <k3-avs.h>
 #include <dm/device_compat.h>
 #include <linux/bitops.h>
+#include <linux/delay.h>
 #include <power/regulator.h>
 
 #define AM6_VTM_DEVINFO(i)     (priv->base + 0x100 + 0x20 * (i))
@@ -25,11 +26,28 @@
 #define AM6_VTM_OPP_SHIFT(opp) (8 * (opp))
 #define AM6_VTM_OPP_MASK       0xff
 
+#define K3_VTM_DEVINFO_PWR0_OFFSET             0x4
+#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK   0xf0
+#define K3_VTM_TMPSENS0_CTRL_OFFSET            0x300
+#define K3_VTM_TMPSENS_STAT_OFFSET             0x8
+#define K3_VTM_ANYMAXT_OUTRG_ALERT_EN          0x1
+#define K3_VTM_LOW_TEMP_OFFSET                 0x10
+#define K3_VTM_MISC_CTRL2_OFFSET               0x10
+#define K3_VTM_MISC_CTRL1_OFFSET               0xc
+#define K3_VTM_TMPSENS_CTRL1_SOC               BIT(5)
+#define K3_VTM_TMPSENS_CTRL_CLRZ               BIT(6)
+#define K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN      BIT(11)
+#define K3_VTM_ADC_COUNT_FOR_123C              0x2f8
+#define K3_VTM_ADC_COUNT_FOR_105C              0x288
+#define K3_VTM_ADC_WA_VALUE                    0x2c
+#define K3_VTM_FUSE_MASK                       0xc0000000
+
 #define VD_FLAG_INIT_DONE      BIT(0)
 
 struct k3_avs_privdata {
        void *base;
        struct vd_config *vd_config;
+       struct udevice *dev;
 };
 
 struct opp {
@@ -237,6 +255,88 @@ static int k3_avs_configure(struct udevice *dev, struct k3_avs_privdata *priv)
        return 0;
 }
 
+/* k3_avs_program_tshut : Program thermal shutdown value for SOC
+ * set the values corresponding to thresholds to ~123C and 105C
+ * This is optional feature, Few times OS driver takes care of
+ * tshut programing.
+ */
+
+static void k3_avs_program_tshut(struct k3_avs_privdata *priv)
+{
+       int cnt, id, val;
+       int workaround_needed = 0;
+       u32 ctrl_offset;
+       void __iomem *cfg2_base;
+       void __iomem *fuse_base;
+
+       cfg2_base = (void __iomem *)devfdt_get_addr_index(priv->dev, 1);
+       if (IS_ERR(cfg2_base)) {
+               dev_err(priv->dev, "cfg base is not defined\n");
+               return;
+       }
+
+       /*
+        * Some of TI's J721E SoCs require a software trimming procedure
+        * for the temperature monitors to function properly. To determine
+        * if this particular SoC is NOT affected, both bits in the
+        * WKUP_SPARE_FUSE0[31:30] will be set (0xC0000000) indicating
+        * when software trimming should NOT be applied.
+        *
+        * https://www.ti.com/lit/er/sprz455c/sprz455c.pdf
+        * This routine checks if workaround_needed to be applied or not
+        * based upon workaround_needed, adjust fixed value of tshut high and low
+        */
+
+       if (device_is_compatible(priv->dev, "ti,j721e-vtm")) {
+               fuse_base = (void __iomem *)devfdt_get_addr_index(priv->dev, 2);
+               if (IS_ERR(fuse_base)) {
+                       dev_err(priv->dev, "fuse-base is not defined for J721E Soc\n");
+                       return;
+               }
+
+               if (!((readl(fuse_base) & K3_VTM_FUSE_MASK) == K3_VTM_FUSE_MASK))
+                       workaround_needed = 1;
+       }
+
+       dev_dbg(priv->dev, "Work around %sneeded\n", workaround_needed ? "" : "not ");
+
+       /* Get the sensor count in the VTM */
+       val = readl(priv->base + K3_VTM_DEVINFO_PWR0_OFFSET);
+       cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
+       cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
+
+       /* Program the thermal sensors */
+       for (id = 0; id < cnt; id++) {
+               ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET + id * 0x20;
+
+               val = readl(cfg2_base + ctrl_offset);
+               val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN |
+                       K3_VTM_TMPSENS_CTRL1_SOC |
+                       K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4));
+               writel(val, cfg2_base + ctrl_offset);
+       }
+
+       /*
+        * Program TSHUT thresholds
+        * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2
+        * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN  bit
+        *         This is already taken care as per of init
+        * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN  bit
+        */
+
+       /* Low thresholds for tshut*/
+       val = (K3_VTM_ADC_COUNT_FOR_105C - workaround_needed * K3_VTM_ADC_WA_VALUE)
+               << K3_VTM_LOW_TEMP_OFFSET;
+       /* high thresholds */
+       val |= K3_VTM_ADC_COUNT_FOR_123C - workaround_needed * K3_VTM_ADC_WA_VALUE;
+
+       writel(val, cfg2_base + K3_VTM_MISC_CTRL2_OFFSET);
+       /* ramp-up delay from Linux code */
+       mdelay(100);
+       val = readl(cfg2_base + K3_VTM_MISC_CTRL1_OFFSET) | K3_VTM_ANYMAXT_OUTRG_ALERT_EN;
+       writel(val, cfg2_base + K3_VTM_MISC_CTRL1_OFFSET);
+}
+
 /**
  * k3_avs_probe: parses VD info from VTM, and re-configures the OPP data
  *
@@ -255,6 +355,7 @@ static int k3_avs_probe(struct udevice *dev)
        int ret;
 
        priv = dev_get_priv(dev);
+       priv->dev = dev;
 
        k3_avs_priv = priv;
 
@@ -294,6 +395,9 @@ static int k3_avs_probe(struct udevice *dev)
                k3_avs_program_voltage(priv, vd, vd->opp);
        }
 
+       if (!device_is_compatible(priv->dev, "ti,am654-avs"))
+               k3_avs_program_tshut(priv);
+
        return 0;
 }