timer: gxp: Add HPE GXP timer support

Add support for the HPE GXP SOC timer. The GXP supports several different
kinds of timers but for the purpose of this driver there is only support
for the General Timer. The timer has a 1us resolution and is 56 bits.

Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>

diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig
index 7b8ab56..d592dba 100644 (file)
--- a/drivers/timer/Kconfig
+++ b/drivers/timer/Kconfig
@@ -139,6 +139,13 @@ config DESIGNWARE_APB_TIMER
          Enables support for the Designware APB Timer driver. This timer is
          present on Altera SoCFPGA SoCs.
 
+config GXP_TIMER
+       bool "HPE GXP Timer"
+       depends on TIMER
+       help
+         Enables support for the GXP Timer driver. This timer is
+         present on HPE GXP SoCs.
+
 config MPC83XX_TIMER
        bool "MPC83xx timer support"
        depends on TIMER

diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile
index b2f002d..cc2b851 100644 (file)
--- a/drivers/timer/Makefile
+++ b/drivers/timer/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_$(SPL_)ATMEL_PIT_TIMER) += atmel_pit_timer.o
 obj-$(CONFIG_$(SPL_)ATMEL_TCB_TIMER) += atmel_tcb_timer.o
 obj-$(CONFIG_CADENCE_TTC_TIMER)        += cadence-ttc.o
 obj-$(CONFIG_DESIGNWARE_APB_TIMER)     += dw-apb-timer.o
+obj-$(CONFIG_GXP_TIMER)                += gxp-timer.o
 obj-$(CONFIG_MPC83XX_TIMER) += mpc83xx_timer.o
 obj-$(CONFIG_NOMADIK_MTU_TIMER)        += nomadik-mtu-timer.o
 obj-$(CONFIG_NPCM_TIMER)        += npcm-timer.o

diff --git a/drivers/timer/gxp-timer.c b/drivers/timer/gxp-timer.c
new file mode 100644 (file)
index 0000000..6f316bc
--- /dev/null
+++ b/drivers/timer/gxp-timer.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * GXP timer driver
+ *
+ * (C) Copyright 2022 Hewlett Packard Enterprise Development LP.
+ * Author: Nick Hawkins <nick.hawkins@hpe.com>
+ * Author: Jean-Marie Verdun <verdun@hpe.com>
+ */
+
+#include <clk.h>
+#include <dm.h>
+#include <timer.h>
+#include <asm/io.h>
+
+#define USTIMELO       0x18
+#define USTIMEHI       0x1C
+
+struct gxp_timer_priv {
+       void __iomem *base;
+};
+
+static u64 gxp_timer_get_count(struct udevice *dev)
+{
+       struct gxp_timer_priv *priv = dev_get_priv(dev);
+       u64 val;
+
+       val = readl(priv->base + USTIMEHI);
+       val = (val << 32) | readl(priv->base + USTIMELO);
+
+       return val;
+}
+
+static int gxp_timer_probe(struct udevice *dev)
+{
+       struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+       struct gxp_timer_priv *priv = dev_get_priv(dev);
+
+       priv->base = dev_read_addr_ptr(dev);
+       if (!priv->base)
+               return -ENOENT;
+
+       uc_priv->clock_rate = 1000000;
+
+       return 0;
+}
+
+static const struct timer_ops gxp_timer_ops = {
+       .get_count = gxp_timer_get_count,
+};
+
+static const struct udevice_id gxp_timer_ids[] = {
+       { .compatible = "hpe,gxp-timer" },
+       {}
+};
+
+U_BOOT_DRIVER(gxp_timer) = {
+       .name = "gxp-timer",
+       .id = UCLASS_TIMER,
+       .of_match = gxp_timer_ids,
+       .priv_auto = sizeof(struct gxp_timer_priv),
+       .probe = gxp_timer_probe,
+       .ops = &gxp_timer_ops,
+       .flags = DM_FLAG_PRE_RELOC,
+};