serial: msm-geni: don't rely on parent misc device

commit 1b15483deb3f ("misc: add Qualcomm GENI SE QUP device driver")
introduced support for platform-specific oversampling values, necessary
to configure the UART clocks on all platforms at runtime. However it
relies in probing a parent device. Despite the DM_FLAG_PRE_RELOC flag,
this is not done consistently during boot.

Instead, take another approach by relying on ofnode_ helpers to read the
serial engine base address and do the read directly. This fixes early
UART on boards with a non-default oversampling rate.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index e8e4400516f8318c19cb37f4aaecb8b232310296..e85a0dd51ca5f1c4ab1f16e06c38057a40414347 100644 (file)
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -527,13 +527,6 @@ config WINBOND_W83627
          legacy UART or other devices in the Winbond Super IO chips
          on X86 platforms.
 
-config QCOM_GENI_SE
-       bool "Qualcomm GENI Serial Engine Driver"
-       depends on ARCH_SNAPDRAGON
-       help
-         The driver manages Generic Interface (GENI) firmware based
-         Qualcomm Technologies, Inc. Universal Peripheral (QUP) Wrapper.
-
 config QFW
        bool
        help

diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index cda701d38ec226a010d3b28eb9680fd948d81e1a..6bf1e79f7e291ba4544d79a12ad23c4f7af106c2 100644 (file)
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -60,7 +60,6 @@ obj-$(CONFIG_NUVOTON_NCT6102D) += nuvoton_nct6102d.o
 obj-$(CONFIG_P2SB) += p2sb-uclass.o
 obj-$(CONFIG_PCA9551_LED) += pca9551_led.o
 obj-$(CONFIG_$(SPL_)PWRSEQ) += pwrseq-uclass.o
-obj-$(CONFIG_QCOM_GENI_SE) += qcom-geni-se.o
 ifdef CONFIG_QFW
 obj-y += qfw.o
 obj-$(CONFIG_QFW_ACPI) += qfw_acpi.o

diff --git a/drivers/misc/qcom-geni-se.c b/drivers/misc/qcom-geni-se.c
deleted file mode 100644 (file)
index 281a5ec..0000000
--- a/drivers/misc/qcom-geni-se.c
+++ /dev/null
@@ -1,41 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Qualcomm Generic Interface (GENI) Serial Engine (SE) Wrapper
- *
- * Copyright (C) 2023 Linaro Ltd. <vladimir.zapolskiy@linaro.org>
- */
-
-#include <common.h>
-#include <dm.h>
-#include <misc.h>
-#include <asm/io.h>
-
-static int geni_se_qup_read(struct udevice *dev, int offset,
-                           void *buf, int size)
-{
-       fdt_addr_t base = dev_read_addr(dev);
-
-       if (size != sizeof(u32))
-               return -EINVAL;
-
-       *(u32 *)buf = readl(base + offset);
-
-       return size;
-}
-
-static struct misc_ops geni_se_qup_ops = {
-       .read = geni_se_qup_read,
-};
-
-static const struct udevice_id geni_se_qup_ids[] = {
-       { .compatible = "qcom,geni-se-qup" },
-       {}
-};
-
-U_BOOT_DRIVER(geni_se_qup) = {
-       .name = "geni_se_qup",
-       .id = UCLASS_MISC,
-       .of_match = geni_se_qup_ids,
-       .ops = &geni_se_qup_ops,
-       .flags  = DM_FLAG_PRE_RELOC,
-};

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 6628a887de7ccd50d2a1c02cba0c2689a8ce0536..26460c4e0cab6116a3a79e6a6ab0a7029107d0b9 100644 (file)
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -972,8 +972,6 @@ config MSM_SERIAL
 
 config MSM_GENI_SERIAL
        bool "Qualcomm on-chip GENI UART"
-       select MISC
-       imply QCOM_GENI_SE
        help
          Support UART based on Generic Interface (GENI) Serial Engine (SE),
          used on Qualcomm Snapdragon SoCs. Should support all qualcomm SOCs

diff --git a/drivers/serial/serial_msm_geni.c b/drivers/serial/serial_msm_geni.c
index b8bc61451a01d60c83c42d3cd5542a7fc19496f2..0e52e32ddf3b9de0ad692a640022b5e35138648c 100644 (file)
--- a/drivers/serial/serial_msm_geni.c
+++ b/drivers/serial/serial_msm_geni.c
@@ -485,12 +485,12 @@ static const struct dm_serial_ops msm_serial_ops = {
        .setbrg = msm_serial_setbrg,
 };
 
-static void geni_set_oversampling(struct udevice *dev)
+static int geni_set_oversampling(struct udevice *dev)
 {
        struct msm_serial_data *priv = dev_get_priv(dev);
-       struct udevice *parent_dev = dev_get_parent(dev);
+       ofnode parent_node = ofnode_get_parent(dev_ofnode(dev));
        u32 geni_se_version;
-       int ret;
+       fdt_addr_t addr;
 
        priv->oversampling = UART_OVERSAMPLING;
 
@@ -498,16 +498,20 @@ static void geni_set_oversampling(struct udevice *dev)
         * It could happen that GENI SE IP is missing in the board's device
         * tree or GENI UART node is a direct child of SoC device tree node.
         */
-       if (device_get_uclass_id(parent_dev) != UCLASS_MISC)
-               return;
+       if (!ofnode_device_is_compatible(parent_node, "qcom,geni-se-qup")) {
+               pr_err("%s: UART node must be a child of geniqup node\n",
+                      __func__);
+               return -ENODEV;
+       }
 
-       ret = misc_read(parent_dev, QUP_HW_VER_REG,
-                       &geni_se_version, sizeof(geni_se_version));
-       if (ret != sizeof(geni_se_version))
-               return;
+       /* Read the HW_VER register relative to the parents address space */
+       addr = ofnode_get_addr(parent_node);
+       geni_se_version = readl(addr + QUP_HW_VER_REG);
 
        if (geni_se_version >= QUP_SE_VERSION_2_5)
                priv->oversampling /= 2;
+
+       return 0;
 }
 
 static inline void geni_serial_init(struct udevice *dev)
@@ -552,8 +556,11 @@ static inline void geni_serial_init(struct udevice *dev)
 static int msm_serial_probe(struct udevice *dev)
 {
        struct msm_serial_data *priv = dev_get_priv(dev);
+       int ret;
 
-       geni_set_oversampling(dev);
+       ret = geni_set_oversampling(dev);
+       if (ret < 0)
+               return ret;
 
        /* No need to reinitialize the UART after relocation */
        if (gd->flags & GD_FLG_RELOC)