[PATCH v2 3/3] ARM: tegra: Initialize flow controller from DT
Thierry Reding
thierry.reding at gmail.com
Fri Jun 27 05:07:28 PDT 2014
From: Thierry Reding <treding at nvidia.com>
Use a matching device tree node to initialize the flow controller driver
instead of hard-coding the I/O address. This is necessary to get rid of
the iomap.h include, which in turn make it easier to share this code
with 64-bit Tegra SoCs.
Signed-off-by: Thierry Reding <treding at nvidia.com>
---
Changes in v2:
- implement fallback when the device tree node is missing
- while at it, reorder includes alphabetically
arch/arm/mach-tegra/flowctrl.c | 48 ++++++++++++++++++++++++++++++++++--------
arch/arm/mach-tegra/flowctrl.h | 2 ++
arch/arm/mach-tegra/tegra.c | 2 ++
3 files changed, 43 insertions(+), 9 deletions(-)
diff --git a/arch/arm/mach-tegra/flowctrl.c b/arch/arm/mach-tegra/flowctrl.c
index 4b31091f0d40..89d13b2fa0b5 100644
--- a/arch/arm/mach-tegra/flowctrl.c
+++ b/arch/arm/mach-tegra/flowctrl.c
@@ -18,14 +18,15 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/cpumask.h>
#include <linux/init.h>
-#include <linux/kernel.h>
#include <linux/io.h>
-#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/tegra-soc.h>
#include "flowctrl.h"
-#include "iomap.h"
static u8 flowctrl_offset_halt_cpu[] = {
FLOW_CTRL_HALT_CPU0_EVENTS,
@@ -41,23 +42,22 @@ static u8 flowctrl_offset_cpu_csr[] = {
FLOW_CTRL_CPU1_CSR + 16,
};
+static void __iomem *tegra_flowctrl_base;
+
static void flowctrl_update(u8 offset, u32 value)
{
- void __iomem *addr = IO_ADDRESS(TEGRA_FLOW_CTRL_BASE) + offset;
-
- writel(value, addr);
+ writel(value, tegra_flowctrl_base + offset);
/* ensure the update has reached the flow controller */
wmb();
- readl_relaxed(addr);
+ readl_relaxed(tegra_flowctrl_base + offset);
}
u32 flowctrl_read_cpu_csr(unsigned int cpuid)
{
u8 offset = flowctrl_offset_cpu_csr[cpuid];
- void __iomem *addr = IO_ADDRESS(TEGRA_FLOW_CTRL_BASE) + offset;
- return readl(addr);
+ return readl(tegra_flowctrl_base + offset);
}
void flowctrl_write_cpu_csr(unsigned int cpuid, u32 value)
@@ -138,3 +138,33 @@ void flowctrl_cpu_suspend_exit(unsigned int cpuid)
reg |= FLOW_CTRL_CSR_EVENT_FLAG; /* clear event */
flowctrl_write_cpu_csr(cpuid, reg);
}
+
+static const struct of_device_id matches[] __initconst = {
+ { .compatible = "nvidia,tegra124-flowctrl" },
+ { .compatible = "nvidia,tegra114-flowctrl" },
+ { .compatible = "nvidia,tegra30-flowctrl" },
+ { .compatible = "nvidia,tegra20-flowctrl" },
+ { }
+};
+
+void __init tegra_flowctrl_init(void)
+{
+ /* hardcoded fallback if device tree node is missing */
+ unsigned long base = 0x60007000;
+ unsigned long size = SZ_4K;
+ struct device_node *np;
+
+ np = of_find_matching_node(NULL, matches);
+ if (np) {
+ struct resource res;
+
+ if (of_address_to_resource(np, 0, &res) == 0) {
+ size = resource_size(&res);
+ base = res.start;
+ }
+
+ of_node_put(np);
+ }
+
+ tegra_flowctrl_base = ioremap_nocache(base, size);
+}
diff --git a/arch/arm/mach-tegra/flowctrl.h b/arch/arm/mach-tegra/flowctrl.h
index c89aac60a143..73a9c5016c1a 100644
--- a/arch/arm/mach-tegra/flowctrl.h
+++ b/arch/arm/mach-tegra/flowctrl.h
@@ -59,6 +59,8 @@ void flowctrl_write_cpu_halt(unsigned int cpuid, u32 value);
void flowctrl_cpu_suspend_enter(unsigned int cpuid);
void flowctrl_cpu_suspend_exit(unsigned int cpuid);
+
+void tegra_flowctrl_init(void);
#endif
#endif
diff --git a/arch/arm/mach-tegra/tegra.c b/arch/arm/mach-tegra/tegra.c
index 76a6779c5f84..8e139e246526 100644
--- a/arch/arm/mach-tegra/tegra.c
+++ b/arch/arm/mach-tegra/tegra.c
@@ -46,6 +46,7 @@
#include "board.h"
#include "common.h"
#include "cpuidle.h"
+#include "flowctrl.h"
#include "iomap.h"
#include "irq.h"
#include "pmc.h"
@@ -78,6 +79,7 @@ static void __init tegra_init_early(void)
tegra_cpu_reset_handler_init();
tegra_powergate_init();
tegra_hotplug_init();
+ tegra_flowctrl_init();
}
static void __init tegra_dt_init_irq(void)
--
2.0.0
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