drm/i915: Use mul_u32_u32() more

We have a lot of '(u64)foo * bar' everywhere. Replace with
mul_u32_u32() to avoid gcc failing to use a regular 32x32->64
multiply for this.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190408152702.4153-1-ville.syrjala@linux.intel.comReviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_fixed.h

@@ -71,7 +71,7 @@ static inline u32 mul_round_up_u32_fixed16(u32 val, uint_fixed_16_16_t mul)
 {
 	u64 tmp;
 
-	tmp = (u64)val * mul.val;
+	tmp = mul_u32_u32(val, mul.val);
 	tmp = DIV_ROUND_UP_ULL(tmp, 1 << 16);
 	WARN_ON(tmp > U32_MAX);
 
@@ -83,7 +83,7 @@ static inline uint_fixed_16_16_t mul_fixed16(uint_fixed_16_16_t val,
 {
 	u64 tmp;
 
-	tmp = (u64)val.val * mul.val;
+	tmp = mul_u32_u32(val.val, mul.val);
 	tmp = tmp >> 16;
 
 	return clamp_u64_to_fixed16(tmp);
@@ -114,7 +114,7 @@ static inline uint_fixed_16_16_t mul_u32_fixed16(u32 val, uint_fixed_16_16_t mul
 {
 	u64 tmp;
 
-	tmp = (u64)val * mul.val;
+	tmp = mul_u32_u32(val, mul.val);
 
 	return clamp_u64_to_fixed16(tmp);
 }

drivers/gpu/drm/i915/intel_display.c

@@ -575,7 +575,7 @@ int chv_calc_dpll_params(int refclk, struct dpll *clock)
 	clock->p = clock->p1 * clock->p2;
 	if (WARN_ON(clock->n == 0 || clock->p == 0))
 		return 0;
-	clock->vco = DIV_ROUND_CLOSEST_ULL((u64)refclk * clock->m,
+	clock->vco = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(refclk, clock->m),
 					   clock->n << 22);
 	clock->dot = DIV_ROUND_CLOSEST(clock->vco, clock->p);
 
@@ -960,8 +960,8 @@ chv_find_best_dpll(const struct intel_limit *limit,
 
 			clock.p = clock.p1 * clock.p2;
 
-			m2 = DIV_ROUND_CLOSEST_ULL(((u64)target * clock.p *
-					clock.n) << 22, refclk * clock.m1);
+			m2 = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(target, clock.p * clock.n) << 22,
+						   refclk * clock.m1);
 
 			if (m2 > INT_MAX/clock.m1)
 				continue;
@@ -6946,7 +6946,7 @@ static u32 ilk_pipe_pixel_rate(const struct intel_crtc_state *pipe_config)
 		if (WARN_ON(!pfit_w || !pfit_h))
 			return pixel_rate;
 
-		pixel_rate = div_u64((u64)pixel_rate * pipe_w * pipe_h,
+		pixel_rate = div_u64(mul_u32_u32(pixel_rate, pipe_w * pipe_h),
 				     pfit_w * pfit_h);
 	}
 
@@ -7066,7 +7066,7 @@ static void compute_m_n(unsigned int m, unsigned int n,
 	else
 		*ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX);
 
-	*ret_m = div_u64((u64)m * *ret_n, n);
+	*ret_m = div_u64(mul_u32_u32(m, *ret_n), n);
 	intel_reduce_m_n_ratio(ret_m, ret_n);
 }
 

drivers/gpu/drm/i915/intel_dpll_mgr.c

@@ -2743,11 +2743,11 @@ static bool icl_calc_mg_pll_state(struct intel_crtc_state *crtc_state)
 	}
 
 	if (use_ssc) {
-		tmp = (u64)dco_khz * 47 * 32;
+		tmp = mul_u32_u32(dco_khz, 47 * 32);
 		do_div(tmp, refclk_khz * m1div * 10000);
 		ssc_stepsize = tmp;
 
-		tmp = (u64)dco_khz * 1000;
+		tmp = mul_u32_u32(dco_khz, 1000);
 		ssc_steplen = DIV_ROUND_UP_ULL(tmp, 32 * 2 * 32);
 	} else {
 		ssc_stepsize = 0;

drivers/gpu/drm/i915/intel_pm.c

@@ -678,7 +678,7 @@ static unsigned int intel_wm_method1(unsigned int pixel_rate,
 {
 	u64 ret;
 
-	ret = (u64)pixel_rate * cpp * latency;
+	ret = mul_u32_u32(pixel_rate, cpp * latency);
 	ret = DIV_ROUND_UP_ULL(ret, 10000);
 
 	return ret;