ARM: tegra: don't exceed AVP limits when configuring PLLP
Based on the Tegra TRM, the system clock (which is the AVP clock) can
run up to 275MHz. On power on, the default sytem clock source is set to
PLLP_OUT0. In function clock_early_init(), PLLP_OUT0 will be set to
408MHz which is beyond system clock's upper limit.
The fix is to set the system clock to CLK_M before initializing PLLP,
and then switch back to PLLP_OUT4, which has an appropriate divider
configured, after PLLP has been configured
Implement this logic in new function tegra30_set_up_pllp(),
which sets up PLLP and all PLLP_OUT* dividers, and handles the AVP
clock switching. Remove the duplicate PLLP setup from pllx_set_rate()
and adjust_pllp_out_freqs().
Signed-off-by: Jimmy Zhang <jimmzhang@nvidia.com>
[swarren, significantly refactored the change]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/cpu/arm720t/tegra-common/cpu.c b/arch/arm/cpu/arm720t/tegra-common/cpu.c
index 72c69b9..03f67b1 100644
--- a/arch/arm/cpu/arm720t/tegra-common/cpu.c
+++ b/arch/arm/cpu/arm720t/tegra-common/cpu.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2010-2012, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (c) 2010-2014, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
@@ -114,24 +114,6 @@
},
};
-void adjust_pllp_out_freqs(void)
-{
- struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
- struct clk_pll *pll = &clkrst->crc_pll[CLOCK_ID_PERIPH];
- u32 reg;
-
- /* Set T30 PLLP_OUT1, 2, 3 & 4 freqs to 9.6, 48, 102 & 204MHz */
- reg = readl(&pll->pll_out[0]); /* OUTA, contains OUT2 / OUT1 */
- reg |= (IN_408_OUT_48_DIVISOR << PLLP_OUT2_RATIO) | PLLP_OUT2_OVR
- | (IN_408_OUT_9_6_DIVISOR << PLLP_OUT1_RATIO) | PLLP_OUT1_OVR;
- writel(reg, &pll->pll_out[0]);
-
- reg = readl(&pll->pll_out[1]); /* OUTB, contains OUT4 / OUT3 */
- reg |= (IN_408_OUT_204_DIVISOR << PLLP_OUT4_RATIO) | PLLP_OUT4_OVR
- | (IN_408_OUT_102_DIVISOR << PLLP_OUT3_RATIO) | PLLP_OUT3_OVR;
- writel(reg, &pll->pll_out[1]);
-}
-
int pllx_set_rate(struct clk_pll_simple *pll , u32 divn, u32 divm,
u32 divp, u32 cpcon)
{
@@ -207,12 +189,6 @@
/* set pllx */
sel = &tegra_pll_x_table[chip_sku][osc];
pllx_set_rate(pll, sel->n, sel->m, sel->p, sel->cpcon);
-
- /* adjust PLLP_out1-4 on T3x/T114 */
- if (soc_type >= CHIPID_TEGRA30) {
- debug(" init_pllx: adjusting PLLP out freqs\n");
- adjust_pllp_out_freqs();
- }
}
void enable_cpu_clock(int enable)