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ARC: [plat-axs103] refactor the DT fudging code 

with clk frequency setting code gone by prev commits, we can elide the
unconditonal DT parsing to the specific case of quad core config where
we possibly need to fudge the DT value.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta 2017-08-22 14:37:22 -07:00
parent f6a09bace0
commit 0fa400cb8a
1 changed files with 21 additions and 23 deletions
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44
arch/arc/plat-axs10x/axs10x.c
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@ -309,38 +309,36 @@ static void __init axs101_early_init(void)
static void __init axs103_early_init(void)
{
/*
* TODO: use cpu node "cpu-freq" param instead of platform-specific
* "/cpu_card/core_clk" as it works only if we use fixed-clock for cpu.
*/
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;
#ifdef CONFIG_ARC_MCIP
/*
* AXS103 configurations for SMP/QUAD configurations share device tree
* which defaults to 100 MHz. However recent failures of Quad config
* revealed P&R timing violations so clamp it down to safe 50 MHz
* Instead of duplicating defconfig/DT for SMP/QUAD, add a small hack
*
* This hack is really hacky as of now. Fix it properly by getting the
* number of cores as return value of platform's early SMP callback
* of fudging the freq in DT
*/
#ifdef CONFIG_ARC_MCIP
unsigned int num_cores = (read_aux_reg(ARC_REG_MCIP_BCR) >> 16) & 0x3F;
if (num_cores > 2)
freq = 50;
#endif
if (num_cores > 2) {
u32 freq = 50, orig;
/*
* TODO: use cpu node "cpu-freq" param instead of platform-specific
* "/cpu_card/core_clk" as it works only if we use fixed-clock for cpu.
*/
int off = fdt_path_offset(initial_boot_params, "/cpu_card/core_clk");
const struct fdt_property *prop;
/* 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));
prop = fdt_get_property(initial_boot_params, off,
"clock-frequency", NULL);
orig = be32_to_cpu(*(u32*)(prop->data)) / 1000000;
/* Patching .dtb in-place with new core clock value */
if (freq != orig ) {
freq = cpu_to_be32(freq * 1000000);
fdt_setprop_inplace(initial_boot_params, off,
"clock-frequency", &freq, sizeof(freq));
}
}
#endif
/* Memory maps already config in pre-bootloader */