int smiapp_pll_calculate(struct device *dev,
const struct smiapp_pll_limits *limits,
struct smiapp_pll *pll)
{
uint16_t min_pre_pll_clk_div;
uint16_t max_pre_pll_clk_div;
uint32_t lane_op_clock_ratio, lane_vt_clock_ratio;
uint32_t mul, div;
unsigned int i;
int rval = -EINVAL;
dev_dbg(dev, "binning: %ux%u\n", pll->binning_horizontal,
pll->binning_vertical);
if (pll->flags & SMIAPP_PLL_FLAG_OP_PIX_CLOCK_PER_LANE)
lane_op_clock_ratio = pll->csi2.lanes;
else
lane_op_clock_ratio = 1;
dev_dbg(dev, "lane_op_clock_ratio: %u\n", lane_op_clock_ratio);
if (pll->flags & SMIAPP_PLL_FLAG_VT_PIX_CLOCK_PER_LANE)
lane_vt_clock_ratio = pll->csi2.lanes;
else
lane_vt_clock_ratio = 1;
dev_dbg(dev, "lane_vt_clock_ratio: %u\n", lane_vt_clock_ratio);
switch (pll->bus_type) {
case SMIAPP_PLL_BUS_TYPE_CSI2:
/* CSI transfers 2 bits per clock per lane; thus times 2 */
pll->pll_op_clk_freq_hz = pll->link_freq * 2
* (pll->csi2.lanes / lane_op_clock_ratio);
break;
case SMIAPP_PLL_BUS_TYPE_PARALLEL:
pll->pll_op_clk_freq_hz = div_u64(
pll->link_freq * pll->bits_per_pixel,
DIV_ROUND_UP(pll->bits_per_pixel,
pll->parallel.bus_width));
break;
default:
return -EINVAL;
}
/*
* Half op pix divisor will give us double the rate compared
* to the regular case. Thus divide the desired pll op clock
* frequency by two.
*/
if (pll->flags & SMIAPP_PLL_FLAG_OP_PIX_DIV_HALF)
pll->pll_op_clk_freq_hz /= 2;
/*
* If it'll be multiplied by two in the end divide it now to
* avoid achieving double the desired clock.
*/
if (pll->flags & SMIAPP_PLL_FLAG_PIX_CLOCK_DOUBLE)
pll->pll_op_clk_freq_hz /= 2;
/* Figure out limits for pre-pll divider based on extclk */
dev_dbg(dev, "min / max pre_pll_clk_div: %u / %u\n",
limits->min_pre_pll_clk_div, limits->max_pre_pll_clk_div);
max_pre_pll_clk_div =
min_t(uint16_t, limits->max_pre_pll_clk_div,
clk_div(
pll->ext_clk_freq_hz /
limits->min_pll_ip_freq_hz,
pll->flags
& SMIAPP_PLL_FLAG_ALLOW_ODD_PRE_PLL_CLK_DIV));
min_pre_pll_clk_div =
max_t(uint16_t, limits->min_pre_pll_clk_div,
clk_div_up(
DIV_ROUND_UP(pll->ext_clk_freq_hz,
limits->max_pll_ip_freq_hz),
pll->flags
& SMIAPP_PLL_FLAG_ALLOW_ODD_PRE_PLL_CLK_DIV));
dev_dbg(dev, "pre-pll check: min / max pre_pll_clk_div: %d / %d\n",
min_pre_pll_clk_div, max_pre_pll_clk_div);
i = gcd(pll->pll_op_clk_freq_hz, pll->ext_clk_freq_hz);
mul = div_u64(pll->pll_op_clk_freq_hz, i);
div = pll->ext_clk_freq_hz / i;
dev_dbg(dev, "mul %u / div %u\n", mul, div);
min_pre_pll_clk_div =
max_t(uint16_t, min_pre_pll_clk_div,
clk_div_up(
DIV_ROUND_UP(mul * pll->ext_clk_freq_hz,
limits->max_pll_op_freq_hz),
pll->flags
& SMIAPP_PLL_FLAG_ALLOW_ODD_PRE_PLL_CLK_DIV));
dev_dbg(dev, "pll_op check: min / max pre_pll_clk_div: %d / %d\n",
min_pre_pll_clk_div, max_pre_pll_clk_div);
for (pll->pre_pll_clk_div = min_pre_pll_clk_div;
pll->pre_pll_clk_div <= max_pre_pll_clk_div;
pll->pre_pll_clk_div +=
pll->flags & SMIAPP_PLL_FLAG_ALLOW_ODD_PRE_PLL_CLK_DIV
? 1 : (2 - (pll->pre_pll_clk_div & 1))) {
rval = __smiapp_pll_calculate(dev, limits, pll, mul, div,
lane_op_clock_ratio,
lane_vt_clock_ratio);
if (rval)
continue;
print_pll(dev, pll);
return 0;
}
dev_info(dev, "unable to compute pre_pll divisor\n");
return rval;
}
int smiapp_pll_calculate(struct device *dev,
const struct smiapp_pll_limits *limits,
struct smiapp_pll *pll)
{
const struct smiapp_pll_branch_limits *op_limits = &limits->op;
struct smiapp_pll_branch *op_pll = &pll->op;
uint16_t min_pre_pll_clk_div;
uint16_t max_pre_pll_clk_div;
uint32_t lane_op_clock_ratio;
uint32_t mul, div;
unsigned int i;
int rval = -EINVAL;
if (pll->flags & SMIAPP_PLL_FLAG_NO_OP_CLOCKS) {
/*
* If there's no OP PLL at all, use the VT values
* instead. The OP values are ignored for the rest of
* the PLL calculation.
*/
op_limits = &limits->vt;
op_pll = &pll->vt;
}
if (pll->flags & SMIAPP_PLL_FLAG_OP_PIX_CLOCK_PER_LANE)
lane_op_clock_ratio = pll->csi2.lanes;
else
lane_op_clock_ratio = 1;
dev_dbg(dev, "lane_op_clock_ratio: %u\n", lane_op_clock_ratio);
dev_dbg(dev, "binning: %ux%u\n", pll->binning_horizontal,
pll->binning_vertical);
switch (pll->bus_type) {
case SMIAPP_PLL_BUS_TYPE_CSI2:
/* CSI transfers 2 bits per clock per lane; thus times 2 */
pll->pll_op_clk_freq_hz = pll->link_freq * 2
* (pll->csi2.lanes / lane_op_clock_ratio);
break;
case SMIAPP_PLL_BUS_TYPE_PARALLEL:
pll->pll_op_clk_freq_hz = pll->link_freq * pll->bits_per_pixel
/ DIV_ROUND_UP(pll->bits_per_pixel,
pll->parallel.bus_width);
break;
default:
return -EINVAL;
}
/* Figure out limits for pre-pll divider based on extclk */
dev_dbg(dev, "min / max pre_pll_clk_div: %u / %u\n",
limits->min_pre_pll_clk_div, limits->max_pre_pll_clk_div);
max_pre_pll_clk_div =
min_t(uint16_t, limits->max_pre_pll_clk_div,
clk_div_even(pll->ext_clk_freq_hz /
limits->min_pll_ip_freq_hz));
min_pre_pll_clk_div =
max_t(uint16_t, limits->min_pre_pll_clk_div,
clk_div_even_up(
DIV_ROUND_UP(pll->ext_clk_freq_hz,
limits->max_pll_ip_freq_hz)));
dev_dbg(dev, "pre-pll check: min / max pre_pll_clk_div: %u / %u\n",
min_pre_pll_clk_div, max_pre_pll_clk_div);
i = gcd(pll->pll_op_clk_freq_hz, pll->ext_clk_freq_hz);
mul = div_u64(pll->pll_op_clk_freq_hz, i);
div = pll->ext_clk_freq_hz / i;
dev_dbg(dev, "mul %u / div %u\n", mul, div);
min_pre_pll_clk_div =
max_t(uint16_t, min_pre_pll_clk_div,
clk_div_even_up(
DIV_ROUND_UP(mul * pll->ext_clk_freq_hz,
limits->max_pll_op_freq_hz)));
dev_dbg(dev, "pll_op check: min / max pre_pll_clk_div: %u / %u\n",
min_pre_pll_clk_div, max_pre_pll_clk_div);
for (pll->pre_pll_clk_div = min_pre_pll_clk_div;
pll->pre_pll_clk_div <= max_pre_pll_clk_div;
pll->pre_pll_clk_div += 2 - (pll->pre_pll_clk_div & 1)) {
rval = __smiapp_pll_calculate(dev, limits, op_limits, pll,
op_pll, mul, div,
lane_op_clock_ratio);
if (rval)
continue;
print_pll(dev, pll);
return 0;
}
dev_dbg(dev, "unable to compute pre_pll divisor\n");
return rval;
}