From 35b614684d2f23af525cdc3d800b760d70bd63d3 Mon Sep 17 00:00:00 2001 From: Alexey Brodkin Date: Mon, 1 Feb 2016 17:30:17 +0300 Subject: [PATCH] ARC: [plat-axs] Don't use arc_{get|set}_core_freq() for manipulating core clk For AXS103, certain bitfile configurations may not work with stock "clock-frequency" specified in DT. Instead of duplicating the DT files, we fixup the DT in-place. This used to be done differently - as in top level "clock-frequency" was read very early from FDT and exported using arc_{get|set}_core_freq() also used in setting up clockevent/clocksource timers This homebrew clk API served well for legacy timer probe (non DT) However TIMERS are now probed from DT and use "core_clk" defined in DT, and thus can no longer use the top level "clock-frequency". This change reduces the number of users of ARC clk hack and paves way for removal. Signed-off-by: Alexey Brodkin [vgupta: broken out of from bigger patch] Signed-off-by: Vineet Gupta --- arch/arc/kernel/setup.c | 12 +++++++----- arch/arc/plat-axs10x/axs10x.c | 27 +++++++++++++++++++++------ 2 files changed, 28 insertions(+), 11 deletions(-) diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index b2921a3bd924..6fff28be695d 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -23,7 +23,6 @@ #include #include #include -#include #include #include @@ -229,10 +228,6 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len) if (tbl->info.id == 0) n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n"); - n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n", - (unsigned int)(arc_get_core_freq() / 1000000), - (unsigned int)(arc_get_core_freq() / 10000) % 100); - n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ", IS_AVAIL1(cpu->extn.timer0, "Timer0 "), IS_AVAIL1(cpu->extn.timer1, "Timer1 "), @@ -487,6 +482,10 @@ static int show_cpuinfo(struct seq_file *m, void *v) { char *str; int cpu_id = ptr_to_cpu(v); + struct device_node *pll = of_find_node_by_name(NULL, "core_clk"); + u32 freq; + + of_property_read_u32(pll, "clock-frequency", &freq); if (!cpu_online(cpu_id)) { seq_printf(m, "processor [%d]\t: Offline\n", cpu_id); @@ -498,6 +497,9 @@ static int show_cpuinfo(struct seq_file *m, void *v) goto done; seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, "CPU speed\t: %u.%02u Mhz\n", + (unsigned int)(freq / 1000000), + (unsigned int)(freq / 10000) % 100); seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n", loops_per_jiffy / (500000 / HZ), diff --git a/arch/arc/plat-axs10x/axs10x.c b/arch/arc/plat-axs10x/axs10x.c index 1b0f0f458a2b..9701c93f315d 100644 --- a/arch/arc/plat-axs10x/axs10x.c +++ b/arch/arc/plat-axs10x/axs10x.c @@ -14,10 +14,11 @@ * */ +#include #include +#include #include -#include #include #include #include @@ -389,6 +390,13 @@ axs103_set_freq(unsigned int id, unsigned int fd, unsigned int od) static void __init axs103_early_init(void) { + int offset = fdt_path_offset(initial_boot_params, "/cpu_card/core_clk"); + const struct fdt_property *prop = fdt_get_property(initial_boot_params, + offset, + "clock-frequency", + NULL); + u32 freq = be32_to_cpu(*(u32*)(prop->data)) / 1000000, orig = freq; + /* * AXS103 configurations for SMP/QUAD configurations share device tree * which defaults to 90 MHz. However recent failures of Quad config @@ -401,12 +409,12 @@ static void __init axs103_early_init(void) #ifdef CONFIG_ARC_MCIP unsigned int num_cores = (read_aux_reg(ARC_REG_MCIP_BCR) >> 16) & 0x3F; if (num_cores > 2) - arc_set_core_freq(50 * 1000000); + freq = 50; else if (num_cores == 2) - arc_set_core_freq(75 * 1000000); + freq = 75; #endif - switch (arc_get_core_freq()/1000000) { + switch (freq) { case 33: axs103_set_freq(1, 1, 1); break; @@ -431,11 +439,18 @@ static void __init axs103_early_init(void) * DT "clock-frequency" might not match with board value. * Hence update it to match the board value. */ - arc_set_core_freq(axs103_get_freq() * 1000000); + freq = axs103_get_freq(); break; } - pr_info("Freq is %dMHz\n", axs103_get_freq()); + pr_info("Freq is %dMHz\n", freq); + + /* Patching .dtb in-place with new core clock value */ + if (freq != orig ) { + freq = cpu_to_be32(freq * 1000000); + fdt_setprop_inplace(initial_boot_params, offset, + "clock-frequency", &freq, sizeof(freq)); + } /* Memory maps already config in pre-bootloader */ -- 2.39.5