From: Dinh Nguyen dinguyen@altera.com
When doing a software reboot, all peripheral clocks must get turned on for the L3 interconnect to work.
This code is needed when doing a "reboot" from user-space and a peripheral clock as been gated off. Why would a peripheral clock get gated? An example use case would be a .ko that gets insmod and rmmod during runtime. The insmod would turn on the IP's clock, and the rmmod would turn off the IP's clock. Doing a "reboot" would cause the system to hang.
5c04b57fe33c ("ARM: socfpga: Enable soft reset") Signed-off-by: Dinh Nguyen dinguyen@altera.com Signed-off-by: Clément Péron peron.clem@gmail.com --- arch/arm/mach-socfpga/core.h | 3 +++ arch/arm/mach-socfpga/socfpga.c | 8 ++++++++ 2 files changed, 11 insertions(+)
diff --git a/arch/arm/mach-socfpga/core.h b/arch/arm/mach-socfpga/core.h index 92cae0a9213f..17c8a97c04d9 100644 --- a/arch/arm/mach-socfpga/core.h +++ b/arch/arm/mach-socfpga/core.h @@ -52,4 +52,7 @@ extern unsigned long socfpga_cpu1start_addr;
#define SOCFPGA_SCU_VIRT_BASE 0xfee00000
+/* Clock manager defines */ +#define SOCFPGA_ENABLE_PLL_REG 0xA0 + #endif diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c index 5fb6f79059a8..c9c881f7c67c 100644 --- a/arch/arm/mach-socfpga/socfpga.c +++ b/arch/arm/mach-socfpga/socfpga.c @@ -31,6 +31,7 @@ void __iomem *sys_manager_base_addr; void __iomem *rst_manager_base_addr; void __iomem *sdr_ctl_base_addr; unsigned long socfpga_cpu1start_addr; +void __iomem *clkmgr_base_addr;
static void __init socfpga_sysmgr_init(void) { @@ -51,6 +52,10 @@ static void __init socfpga_sysmgr_init(void) np = of_find_compatible_node(NULL, NULL, "altr,rst-mgr"); rst_manager_base_addr = of_iomap(np, 0);
+ np = of_find_compatible_node(NULL, NULL, "altr,clk-mgr"); + clkmgr_base_addr = of_iomap(np, 0); + WARN_ON(!clkmgr_base_addr); + np = of_find_compatible_node(NULL, NULL, "altr,sdr-ctl"); sdr_ctl_base_addr = of_iomap(np, 0); } @@ -80,6 +85,9 @@ static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd) { u32 temp;
+ /* Turn on all periph PLL clocks */ + writel(0xffff, clkmgr_base_addr + SOCFPGA_ENABLE_PLL_REG); + temp = readl(rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
if (mode == REBOOT_HARD)