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authorJulius Werner <jwerner@chromium.org>2014-10-06 15:02:12 -0700
committerPatrick Georgi <pgeorgi@google.com>2015-04-08 08:48:03 +0200
commitf8dcdea60973b729bf9eee0fb46dccf1b4b2aeb6 (patch)
tree42e70faf8b8c91e98e13d6f86f95c78e9e9f122a
parent558614d4d38d149865c2186802548eec55a03082 (diff)
downloadcoreboot-f8dcdea60973b729bf9eee0fb46dccf1b4b2aeb6.tar.xz
rk3288: Fix some PLL divisors and improve clock code
This patch does some general cleanup in the Rockchip clock code, and adds some more assertions regarding the PLL VCO and output frequency ranges. It changes all PLL divisors to use the lowest values that can still hit the target frequency, since higher NR values lead to higher jitter and higher NO values increase power draw. Also change DDR3 frequency code to hardcode the optimal divisors for certail frequencies. As a little hack we will interpret 666000000 to actually mean 666666666.6P (and analogous for 533MHz), since that's what you usually want for memory. BUG=chrome-os-partner:32139 TEST=Boot on veyron_pinky rev2, check that dpll_is shown as 666666666 in /sys/kernel/debug/clk/clk_summary. Change-Id: I57d7ef34500984184e010c0cc7d73789338834d4 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 7466ffc035b3f06ac280f412bc496059abf3239c Original-Change-Id: I4f3c39641955a95c6dfbe9334035eb670b138bf0 Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/221801 Reviewed-on: http://review.coreboot.org/9339 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
-rw-r--r--src/soc/rockchip/rk3288/clock.c67
-rw-r--r--src/soc/rockchip/rk3288/timer.h4
2 files changed, 42 insertions, 29 deletions
diff --git a/src/soc/rockchip/rk3288/clock.c b/src/soc/rockchip/rk3288/clock.c
index 37d366f127..bdfe079556 100644
--- a/src/soc/rockchip/rk3288/clock.c
+++ b/src/soc/rockchip/rk3288/clock.c
@@ -21,6 +21,7 @@
#include <stdlib.h>
#include <arch/io.h>
#include <stdint.h>
+#include <string.h>
#include <console/console.h>
#include <delay.h>
#include "clock.h"
@@ -65,15 +66,15 @@ check_member(rk3288_cru_reg, cru_emmc_con[1], 0x021c);
static struct rk3288_cru_reg * const cru_ptr = (void *)CRU_BASE;
#define PLL_DIVISORS(hz, _nr, _no) {\
- .nr = _nr, .nf = (u32)((u64)hz * _nr * _no / (24*MHz)), .no = _no};\
- _Static_assert(((u64)hz * _nr * _no / (24*MHz)) * (24*MHz) /\
- (_nr * _no) == hz,\
- #hz "Hz cannot be hit with PLL divisors in " __FILE__);
+ .nr = _nr, .nf = (u32)((u64)hz * _nr * _no / OSC_HZ), .no = _no};\
+ _Static_assert(((u64)hz * _nr * _no / OSC_HZ) * OSC_HZ /\
+ (_nr * _no) == hz, #hz "Hz cannot be hit with PLL "\
+ "divisors on line " STRINGIFY(__LINE__));
-/* apll = 816MHz, gpll = 594MHz, cpll = 384MHz */
-static const struct pll_div apll_init_cfg = PLL_DIVISORS(APLL_HZ, 1, 2);
-static const struct pll_div gpll_init_cfg = PLL_DIVISORS(GPLL_HZ, 2, 4);
-static const struct pll_div cpll_init_cfg = PLL_DIVISORS(CPLL_HZ, 2, 4);
+/* Keep divisors as low as possible to reduce jitter and power usage. */
+static const struct pll_div apll_init_cfg = PLL_DIVISORS(APLL_HZ, 1, 1);
+static const struct pll_div gpll_init_cfg = PLL_DIVISORS(GPLL_HZ, 2, 2);
+static const struct pll_div cpll_init_cfg = PLL_DIVISORS(CPLL_HZ, 1, 2);
/*******************PLL CON0 BITS***************************/
#define PLL_OD_MSK (0x0F)
@@ -190,19 +191,28 @@ static const struct pll_div cpll_init_cfg = PLL_DIVISORS(CPLL_HZ, 2, 4);
#define SOCSTS_CPLL_LOCK (1 << 7)
#define SOCSTS_GPLL_LOCK (1 << 8)
-static int rkclk_set_pll(u32 *pll_con, const struct pll_div *pll_div_cfg)
+static int rkclk_set_pll(u32 *pll_con, const struct pll_div *div)
{
+ /* All PLLs have same VCO and output frequency range restrictions. */
+ u32 vco_khz = OSC_HZ/KHz * div->nf / div->nr;
+ u32 output_khz = vco_khz / div->no;
+
+ printk(BIOS_DEBUG, "Configuring PLL at %p with NF = %d, NR = %d and "
+ "NO = %d (VCO = %uKHz, output = %uKHz)\n",
+ pll_con, div->nf, div->nr, div->no, vco_khz, output_khz);
+ assert(vco_khz >= 440*(MHz/KHz) && vco_khz <= 2200*(MHz/KHz) &&
+ output_khz >= 27500 && output_khz <= 2200*(MHz/KHz) &&
+ (div->no == 1 || !(div->no % 2)));
+
/* enter rest */
writel(RK_SETBITS(PLL_RESET_MSK), &pll_con[3]);
- writel(RK_CLRSETBITS(PLL_NR_MSK, (pll_div_cfg->nr - 1) << PLL_NR_SHIFT)
- | RK_CLRSETBITS(PLL_OD_MSK, (pll_div_cfg->no - 1)), &pll_con[0]);
+ writel(RK_CLRSETBITS(PLL_NR_MSK, (div->nr - 1) << PLL_NR_SHIFT)
+ | RK_CLRSETBITS(PLL_OD_MSK, (div->no - 1)), &pll_con[0]);
- writel(RK_CLRSETBITS(PLL_NF_MSK, (pll_div_cfg->nf - 1)),
- &pll_con[1]);
+ writel(RK_CLRSETBITS(PLL_NF_MSK, (div->nf - 1)), &pll_con[1]);
- writel(RK_CLRSETBITS(PLL_BWADJ_MSK, ((pll_div_cfg->nf >> 1) - 1)),
- &pll_con[2]);
+ writel(RK_CLRSETBITS(PLL_BWADJ_MSK, ((div->nf >> 1) - 1)), &pll_con[2]);
udelay(10);
@@ -352,20 +362,23 @@ void rkclk_configure_ddr(unsigned int hz)
{
struct pll_div dpll_cfg;
- if (hz <= 150*MHz) {
- dpll_cfg.nr = 3;
- dpll_cfg.no = 8;
- } else if (hz <= 540*MHz) {
- dpll_cfg.nr = 6;
- dpll_cfg.no = 4;
- } else {
- dpll_cfg.nr = 1;
- dpll_cfg.no = 1;
+ switch (hz) {
+ case 300*MHz:
+ dpll_cfg = (struct pll_div){.nf = 25, .nr = 2, .no = 1};
+ break;
+ case 533*MHz: /* actually 533.3P MHz */
+ dpll_cfg = (struct pll_div){.nf = 400, .nr = 9, .no = 2};
+ break;
+ case 666*MHz: /* actually 666.6P MHz */
+ dpll_cfg = (struct pll_div){.nf = 500, .nr = 9, .no = 2};
+ break;
+ case 800*MHz:
+ dpll_cfg = (struct pll_div){.nf = 100, .nr = 3, .no = 1};
+ break;
+ default:
+ die("Unsupported SDRAM frequency, add to clock.c!");
}
- dpll_cfg.nf = (hz/KHz * dpll_cfg.nr * dpll_cfg.no) / (24*KHz);
- assert(dpll_cfg.nf < 4096 && hz == dpll_cfg.nf * (24*KHz) /
- (dpll_cfg.nr * dpll_cfg.no) * 1000);
/* pll enter slow-mode */
writel(RK_CLRSETBITS(DPLL_MODE_MSK, DPLL_MODE_SLOW),
&cru_ptr->cru_mode_con);
diff --git a/src/soc/rockchip/rk3288/timer.h b/src/soc/rockchip/rk3288/timer.h
index 9f1fbaf8c5..85079391e6 100644
--- a/src/soc/rockchip/rk3288/timer.h
+++ b/src/soc/rockchip/rk3288/timer.h
@@ -23,9 +23,9 @@
#include <inttypes.h>
#include <timer.h>
#include "addressmap.h"
+#include "clock.h"
-#define SYS_CLK_FREQ (24*MHz)
-static const u32 clocks_per_usec = SYS_CLK_FREQ/USECS_PER_SEC;
+static const u32 clocks_per_usec = OSC_HZ/USECS_PER_SEC;
struct rk3288_timer {
u32 timer_load_count0;