From d8cadae6b52d168a8b3370b4953a121b48174312 Mon Sep 17 00:00:00 2001 From: Sebastian Pop Date: Wed, 31 May 2017 10:09:45 -0500 Subject: [PATCH 3/3] hi6220-sysconfig: turn on debug mode on all cpus Loop through all cpus and turn on debug mode. Heavily inspired by https://github.com/96boards-hikey/arm-trusted-firmware/commit/543f1db7fd7e0aadcf947adedd63eaed817ef402 Signed-off-by: George Burgess Signed-off-by: Sebastian Pop --- drivers/misc/hi6220-sysconfig.c | 42 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) diff --git a/drivers/misc/hi6220-sysconfig.c b/drivers/misc/hi6220-sysconfig.c index c61bfbb..e8adfa7 100644 --- a/drivers/misc/hi6220-sysconfig.c +++ b/drivers/misc/hi6220-sysconfig.c @@ -4,10 +4,41 @@ #define ACPU_SC_CLKEN 0x00C #define ACPU_SC_CLK_STAT 0x014 +// Heavily inspired by +// https://github.com/96boards-hikey/arm-trusted-firmware/commit/543f1db7fd7e0aadcf947adedd63eaed817ef402 +static int ensure_debug_mode_on(void __iomem *base, unsigned int cpu, + unsigned int cluster) +{ + void __iomem *base_off; + unsigned int data, expected; + // Some number high enough to basically never fail, but also to not lock + // up the system in case my code is broken. + const unsigned int max_loop_retries = 10000; + unsigned int loop_retries = 0; + + base_off = base + 0x02c; + data = readl_relaxed(base_off); + if (cluster) + expected = 1 << (cpu + 8); + else + expected = 1 << cpu; + writel_relaxed((data | expected), base_off); + + for (loop_retries = 0; loop_retries < max_loop_retries; + loop_retries++) { + /* RAW barrier */ + data = readl_relaxed(base_off); + if (data & expected) + break; + } + return loop_retries == max_loop_retries; +} + static int __init hi6220_sysconf(void) { static void __iomem *base = NULL; - + unsigned int cpu, cluster; + base = ioremap(SOC_HI6220_ACPU_SCTRL_BASE_ADDR, SZ_4K); if (base == NULL) { pr_err("hi6220: asctl reg iomap failed!\n"); @@ -21,6 +52,15 @@ static int __init hi6220_sysconf(void) pr_err("%s:after sctrl ACPU_SC_CLK_STAT is %x\n", __func__, readl(base + ACPU_SC_CLK_STAT)); + for (cluster = 0; cluster < 2; cluster++) { + for (cpu = 0; cpu < 4; cpu++) { + if (ensure_debug_mode_on(base, cpu, cluster)) { + pr_err("hi6220: flipping debug mode for cpu %d " + "failed.\n", cpu + cluster*4); + // Keep trying for the remainder anyway. + } + } + } iounmap(base); -- 2.6.3