/*
* Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Shamelessly ripped off from ChromeOS's gk20a/clk_pllg.c
*
*/
#include "priv.h"
#include "gk20a.h"
#include <core/tegra.h>
#include <subdev/timer.h>
static const u8 _pl_to_div[] = {
/* PL: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 */
/* p: */ 1, 2, 3, 4, 5, 6, 8, 10, 12, 16, 12, 16, 20, 24, 32,
};
static u32 pl_to_div(u32 pl)
{
if (pl >= ARRAY_SIZE(_pl_to_div))
return 1;
return _pl_to_div[pl];
}
static u32 div_to_pl(u32 div)
{
u32 pl;
for (pl = 0; pl < ARRAY_SIZE(_pl_to_div) - 1; pl++) {
if (_pl_to_div[pl] >= div)
return pl;
}
return ARRAY_SIZE(_pl_to_div) - 1;
}
static const struct gk20a_clk_pllg_params gk20a_pllg_params = {
.min_vco = 1000000, .max_vco = 2064000,
.min_u = 12000, .max_u = 38000,
.min_m = 1, .max_m = 255,
.min_n = 8, .max_n = 255,
.min_pl = 1, .max_pl = 32,
};
void
gk20a_pllg_read_mnp(struct gk20a_clk *clk, struct gk20a_pll *pll)
{
struct nvkm_device *device = clk->base.subdev.device;
u32 val;
val = nvkm_rd32(device, GPCPLL_COEFF);
pll->m = (val >> GPCPLL_COEFF_M_SHIFT) & MASK(GPCPLL_COEFF_M_WIDTH);
pll->n = (val >> GPCPLL_COEFF_N_SHIFT) & MASK(GPCPLL_COEFF_N_WIDTH);
pll->pl = (val >> GPCPLL_COEFF_P_SHIFT) & MASK(GPCPLL_COEFF_P_WIDTH);
}
void
gk20a_pllg_write_mnp(struct gk20a_clk *clk, const struct gk20a_pll *pll)
{
struct nvkm_device *device = clk->base.subdev.device;
u32 val;
val = (pll->m & MASK(GPCPLL_COEFF_M_WIDTH)) << GPCPLL_COEFF_M_SHIFT;
val |= (pll->n & MASK(GPCPLL_COEFF_N_WIDTH)) << GPCPLL_COEFF_N_SHIFT;
val |= (pll->pl & MASK(GPCPLL_COEFF_P_WIDTH)) << GPCPLL_COEFF_P_SHIFT;
nvkm_wr32(device, GPCPLL_COEFF, val);
}
u32
gk20a_pllg_calc_rate(struct gk20a_clk *clk, struct gk20a_pll *pll)
{
u32 rate;
u32 divider;
rate = clk->parent_rate * pll->n;
divider = pll->m * clk->pl_to_div(pll->pl);
return rate / divider / 2;
}
int
gk20a_pllg_calc_mnp(struct gk20a_clk *clk, unsigned long rate,
struct gk20a_pll *pll)
{
struct nvkm_subdev *subdev = &clk->base.subdev;
u32 target_clk_f, ref_clk_f, target_freq;
u32 min_vco_f, max_vco_f;
u32 low_pl, high_pl, best_pl;
u32 target_vco_f;
u32 best_m, best_n;
u32 best_delta = ~0;
u32 pl;
target_clk_f = rate * 2 / KHZ;
ref_clk_f = clk->parent_rate / KHZ;
target_vco_f = target_clk_f + target_clk_f / 50;
max_vco_f = max(clk->params->max_vco, target_vco_f);
min_vco_f = clk->params->min_vco;
best_m = clk->params->max_m;
best_n = clk->params->min_n;
best_pl = clk->params->min_pl;
/* min_pl <= high_pl <= max_pl */
high_pl = (max_vco_f + target_vco_f - 1) / target_vco_f;
high_pl = min(high_pl, clk->params->max_pl);
high_pl = max(high_pl, clk->params->min_pl);
high_pl = clk->div_to_pl(high_pl);
/* min_pl <= low_pl <= max_pl */
low_pl = min_vco_f / target_vco_f;
low_pl = min(low_pl, clk->params->max_pl);
low_pl = max(low_pl, clk->params->min_pl);
low_pl = clk->div_to_pl(low_pl);
nvkm_debug(subdev, "low_PL %d(div%d), high_PL %d(div%d)", low_pl,
clk->pl_to_div(low_pl), high_pl, clk->pl_to_div(high_pl));
/* Select lowest possible VCO */
for (pl = low_pl; pl <= high_pl; pl++) {
u32 m, n, n2;
target_vco_f = target_clk_f * clk->pl_to_div(pl);
for (m = clk->params->min_m; m <= clk->params->max_m; m++) {
u32 u_f = ref_clk_f / m;
if (u_f < clk->params->min_u)
break;
if (u_f > clk->params->max_u)
continue;
n = (target_vco_f * m) / ref_clk_f;
n2 = ((target_vco_f * m) + (ref_clk_f - 1)) / ref_clk_f;
if (n > clk->params->max_n)
break;
for (; n <= n2; n++) {
u32 vco_f;
if (n < clk->params->min_n)
continue;
if (n > clk->params->max_n)
break;
vco_f = ref_clk_f * n / m;
if (vco_f >= min_vco_f && vco_f <= max_vco_f) {
u32 delta, lwv;
lwv = (vco_f + (clk->pl_to_div(pl) / 2))
/ clk->pl_to_div(pl);
delta = abs(lwv - target_clk_f);
if (delta < best_delta) {
best_delta = delta;
best_m = m;
best_n = n;
best_pl = pl;
if (best_delta == 0)
goto found_match;
}
}
}
}
}
found_match:
WARN_ON(best_delta == ~0);
if (best_delta != 0)
nvkm_debug(subdev,
"no best match for target @ %dMHz on gpc_pll",
target_clk_f / KHZ);
pll->m = best_m;
pll->n = best_n;
pll->pl = best_pl;
target_freq = gk20a_pllg_calc_rate(clk, pll);
nvkm_debug(subdev,
"actual target freq %d KHz, M %d, N %d, PL %d(div%d)\n",
target_freq / KHZ, pll->m, pll->n, pll->pl,
clk->pl_to_div(pll->pl));
return 0;
}
static int
gk20a_pllg_slide(struct gk20a_clk *clk, u32 n)
{
struct nvkm_subdev *subdev = &clk->base.subdev;
struct nvkm_device *device = subdev->device;
struct gk20a_pll pll;
int ret = 0;
/* get old coefficients */
gk20a_pllg_read_mnp(clk, &pll);
/* do nothing if NDIV is the same */
if (n == pll.n)
return 0;
/* pll slowdown mode */
nvkm_mask(device, GPCPLL_NDIV_SLOWDOWN,
BIT(GPCPLL_NDIV_SLOWDOWN_SLOWDOWN_USING_PLL_SHIFT),
BIT(GPCPLL_NDIV_SLOWDOWN_SLOWDOWN_USING_PLL_SHIFT));
/* new ndiv ready for ramp */
pll.n = n;
udelay(1);
gk20a_pllg_write_mnp(clk, &pll);
/* dynamic ramp to new ndiv */
udelay(1);
nvkm_mask(device, GPCPLL_NDIV_SLOWDOWN,
BIT(GPCPLL_NDIV_SLOWDOWN_EN_DYNRAMP_SHIFT),
BIT(GPCPLL_NDIV_SLOWDOWN_EN_DYNRAMP_SHIFT));
/* wait for ramping to complete */
if (nvkm_wait_usec(device, 500, GPC_BCAST_NDIV_SLOWDOWN_DEBUG,
GPC_BCAST_NDIV_SLOWDOWN_DEBUG_PLL_DYNRAMP_DONE_SYNCED_MASK,
GPC_BCAST_NDIV_SLOWDOWN_DEBUG_PLL_DYNRAMP_DONE_SYNCED_MASK) < 0)
ret = -ETIMEDOUT;
/* exit slowdown mode */
nvkm_mask(device, GPCPLL_NDIV_SLOWDOWN,
BIT(GPCPLL_NDIV_SLOWDOWN_SLOWDOWN_USING_PLL_SHIFT) |
BIT(GPCPLL_NDIV_SLOWDOWN_EN_DYNRAMP_SHIFT), 0);
nvkm_rd32(device, GPCPLL_NDIV_SLOWDOWN);
return ret;
}
static int
gk20a_pllg_enable(struct gk20a_clk *clk)
{
struct nvkm_device *device = clk->base.subdev.device;
u32 val;
nvkm_mask(device, GPCPLL_CFG, GPCPLL_CFG_ENABLE, GPCPLL_CFG_ENABLE);
nvkm_rd32(device, GPCPLL_CFG);
/* enable lock detection */
val = nvkm_rd32(device, GPCPLL_CFG);
if (val & GPCPLL_CFG_LOCK_DET_OFF) {
val &= ~GPCPLL_CFG_LOCK_DET_OFF;
nvkm_wr32(device, GPCPLL_CFG, val);
}
/* wait for lock */
if (nvkm_wait_usec(device, 300, GPCPLL_CFG, GPCPLL_CFG_LOCK,
GPCPLL_CFG_LOCK) < 0)
return -ETIMEDOUT;
/* switch to VCO mode */
nvkm_mask(device, SEL_VCO, BIT(SEL_VCO_GPC2CLK_OUT_SHIFT),
BIT(SEL_VCO_GPC2CLK_OUT_SHIFT));
return 0;
}
static void
gk20a_pllg_disable(struct gk20a_clk *clk)
{
struct nvkm_device *device = clk->base.subdev.device;
/* put PLL in bypass before disabling it */
nvkm_mask(device, SEL_VCO, BIT(SEL_VCO_GPC2CLK_OUT_SHIFT), 0);
nvkm_mask(device, GPCPLL_CFG, GPCPLL_CFG_ENABLE, 0);
nvkm_rd32(device, GPCPLL_CFG);
}
static int
gk20a_pllg_program_mnp(struct gk20a_clk *clk, const struct gk20a_pll *pll)
{
struct nvkm_subdev *subdev = &clk->base.subdev;
struct nvkm_device *device = subdev->device;
struct gk20a_pll cur_pll;
int ret;
gk20a_pllg_read_mnp(clk, &cur_pll);
/* split VCO-to-bypass jump in half by setting out divider 1:2 */
nvkm_mask(device, GPC2CLK_OUT, GPC2CLK_OUT_VCODIV_MASK,
GPC2CLK_OUT_VCODIV2 << GPC2CLK_OUT_VCODIV_SHIFT);
/* Intentional 2nd write to assure linear divider operation */
nvkm_mask(device, GPC2CLK_OUT, GPC2CLK_OUT_VCODIV_MASK,
GPC2CLK_OUT_VCODIV2 << GPC2CLK_OUT_VCODIV_SHIFT);
nvkm_rd32(device, GPC2CLK_OUT);
udelay(2);
gk20a_pllg_disable(clk);
gk20a_pllg_write_mnp(clk, pll);
ret = gk20a_pllg_enable(clk);
if (ret)
return ret;
/* restore out divider 1:1 */
udelay(2);
nvkm_mask(device, GPC2CLK_OUT, GPC2CLK_OUT_VCODIV_MASK,
GPC2CLK_OUT_VCODIV1 << GPC2CLK_OUT_VCODIV_SHIFT);
/* Intentional 2nd write to assure linear divider operation */
nvkm_mask(device, GPC2CLK_OUT, GPC2CLK_OUT_VCODIV_MASK,
GPC2CLK_OUT_VCODIV1 << GPC2CLK_OUT_VCODIV_SHIFT);
nvkm_rd32(device, GPC2CLK_OUT);
return 0;
}
static int
gk20a_pllg_program_mnp_slide(struct gk20a_clk *clk, const struct gk20a_pll *pll)
{
struct gk20a_pll cur_pll;
int ret;
if (gk20a_pllg_is_enabled(clk)) {
gk20a_pllg_read_mnp(clk, &cur_pll);
/* just do NDIV slide if there is no change to M and PL */
if (pll->m == cur_pll.m && pll->pl == cur_pll.pl)
return gk20a_pllg_slide(clk, pll->n);
/* slide down to current NDIV_LO */
cur_pll.n = gk20a_pllg_n_lo(clk, &cur_pll);
ret = gk20a_pllg_slide(clk, cur_pll.n);
if (ret)
return ret;
}
/* program MNP with the new clock parameters and new NDIV_LO */
cur_pll = *pll;
cur_pll.n = gk20a_pllg_n_lo(clk, &cur_pll);
ret = gk20a_pllg_program_mnp(clk, &cur_pll);
if (ret)
return ret;
/* slide up to new NDIV */
return gk20a_pllg_slide(clk, pll->n);
}
static struct nvkm_pstate
gk20a_pstates[] = {
{
.base = {
.domain[nv_clk_src_gpc] = 72000,
.voltage = 0,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 108000,
.voltage = 1,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 180000,
.voltage = 2,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 252000,
.voltage = 3,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 324000,
.voltage = 4,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 396000,
.voltage = 5,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 468000,
.voltage = 6,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 540000,
.voltage = 7,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 612000,
.voltage = 8,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 648000,
.voltage = 9,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 684000,
.voltage = 10,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 708000,
.voltage = 11,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 756000,
.voltage = 12,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 804000,
.voltage = 13,
},
},
{
.base = {
.domain[nv_clk_src_gpc] = 852000,
.voltage = 14,
},
},
};
int
gk20a_clk_read(struct nvkm_clk *base, enum nv_clk_src src)
{
struct gk20a_clk *clk = gk20a_clk(base);
struct nvkm_subdev *subdev = &clk->base.subdev;
struct nvkm_device *device = subdev->device;
struct gk20a_pll pll;
switch (src) {
case nv_clk_src_crystal:
return device->crystal;
case nv_clk_src_gpc:
gk20a_pllg_read_mnp(clk, &pll);
return gk20a_pllg_calc_rate(clk, &pll) / GK20A_CLK_GPC_MDIV;
default:
nvkm_error(subdev, "invalid clock source %d\n", src);
return -EINVAL;
}
}
int
gk20a_clk_calc(struct nvkm_clk *base, struct nvkm_cstate *cstate)
{
struct gk20a_clk *clk = gk20a_clk(base);
return gk20a_pllg_calc_mnp(clk, cstate->domain[nv_clk_src_gpc] *
GK20A_CLK_GPC_MDIV, &clk->pll);
}
int
gk20a_clk_prog(struct nvkm_clk *base)
{
struct gk20a_clk *clk = gk20a_clk(base);
int ret;
ret = gk20a_pllg_program_mnp_slide(clk, &clk->pll);
if (ret)
ret = gk20a_pllg_program_mnp(clk, &clk->pll);
return ret;
}
void
gk20a_clk_tidy(struct nvkm_clk *base)
{
}
int
gk20a_clk_setup_slide(struct gk20a_clk *clk)
{
struct nvkm_subdev *subdev = &clk->base.subdev;
struct nvkm_device *device = subdev->device;
u32 step_a, step_b;
switch (clk->parent_rate) {
case 12000000:
case 12800000:
case 13000000:
step_a = 0x2b;
step_b = 0x0b;
break;
case 19200000:
step_a = 0x12;
step_b = 0x08;
break;
case 38400000:
step_a = 0x04;
step_b = 0x05;
break;
default:
nvkm_error(subdev, "invalid parent clock rate %u KHz",
clk->parent_rate / KHZ);
return -EINVAL;
}
nvkm_mask(device, GPCPLL_CFG2, 0xff << GPCPLL_CFG2_PLL_STEPA_SHIFT,
step_a << GPCPLL_CFG2_PLL_STEPA_SHIFT);
nvkm_mask(device, GPCPLL_CFG3, 0xff << GPCPLL_CFG3_PLL_STEPB_SHIFT,
step_b << GPCPLL_CFG3_PLL_STEPB_SHIFT);
return 0;
}
void
gk20a_clk_fini(struct nvkm_clk *base)
{
struct nvkm_device *device = base->subdev.device;
struct gk20a_clk *clk = gk20a_clk(base);
/* slide to VCO min */
if (gk20a_pllg_is_enabled(clk)) {
struct gk20a_pll pll;
u32 n_lo;
gk20a_pllg_read_mnp(clk, &pll);
n_lo = gk20a_pllg_n_lo(clk, &pll);
gk20a_pllg_slide(clk, n_lo);
}
gk20a_pllg_disable(clk);
/* set IDDQ */
nvkm_mask(device, GPCPLL_CFG, GPCPLL_CFG_IDDQ, 1);
}
static int
gk20a_clk_init(struct nvkm_clk *base)
{
struct gk20a_clk *clk = gk20a_clk(base);
struct nvkm_subdev *subdev = &clk->base.subdev;
struct nvkm_device *device = subdev->device;
int ret;
/* get out from IDDQ */
nvkm_mask(device, GPCPLL_CFG, GPCPLL_CFG_IDDQ, 0);
nvkm_rd32(device, GPCPLL_CFG);
udelay(5);
nvkm_mask(device, GPC2CLK_OUT, GPC2CLK_OUT_INIT_MASK,
GPC2CLK_OUT_INIT_VAL);
ret = gk20a_clk_setup_slide(clk);
if (ret)
return ret;
/* Start with lowest frequency */
base->func->calc(base, &base->func->pstates[0].base);
ret = base->func->prog(&clk->base);
if (ret) {
nvkm_error(subdev, "cannot initialize clock\n");
return ret;
}
return 0;
}
static const struct nvkm_clk_func
gk20a_clk = {
.init = gk20a_clk_init,
.fini = gk20a_clk_fini,
.read = gk20a_clk_read,
.calc = gk20a_clk_calc,
.prog = gk20a_clk_prog,
.tidy = gk20a_clk_tidy,
.pstates = gk20a_pstates,
.nr_pstates = ARRAY_SIZE(gk20a_pstates),
.domains = {
{ nv_clk_src_crystal, 0xff },
{ nv_clk_src_gpc, 0xff, 0, "core", GK20A_CLK_GPC_MDIV },
{ nv_clk_src_max }
}
};
int
gk20a_clk_ctor(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,
const struct nvkm_clk_func *func, const struct gk20a_clk_pllg_params *params,
struct gk20a_clk *clk)
{
struct nvkm_device_tegra *tdev = device->func->tegra(device);
int ret;
int i;
/* Finish initializing the pstates */
for (i = 0; i < func->nr_pstates; i++) {
INIT_LIST_HEAD(&func->pstates[i].list);
func->pstates[i].pstate = i + 1;
}
clk->params = params;
clk->parent_rate = clk_get_rate(tdev->clk);
ret = nvkm_clk_ctor(func, device, type, inst, true, &clk->base);
if (ret)
return ret;
nvkm_debug(&clk->base.subdev, "parent clock rate: %d Khz\n",
clk->parent_rate / KHZ);
return 0;
}
int
gk20a_clk_new(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,
struct nvkm_clk **pclk)
{
struct gk20a_clk *clk;
int ret;
clk = kzalloc(sizeof(*clk), GFP_KERNEL);
if (!clk)
return -ENOMEM;
*pclk = &clk->base;
ret = gk20a_clk_ctor(device, type, inst, &gk20a_clk, &gk20a_pllg_params, clk);
clk->pl_to_div = pl_to_div;
clk->div_to_pl = div_to_pl;
return ret;
}
Codebase Browser
linux