Hello Steven,
On 3/14/22 10:54, Steven Lee wrote:
AST2600's HPLL register offset and bit definition are different from
AST2500. Add a hpll calculation function for ast2600 and modify apb frequency
calculation function based on SCU200 register description in ast2600v11.pdf.
It looks good. A few minor comments on the modeling.
Signed-off-by: Steven Lee <steven_...@aspeedtech.com>
---
hw/misc/aspeed_scu.c | 43 ++++++++++++++++++++++++++++++++----
include/hw/misc/aspeed_scu.h | 17 ++++++++++++++
2 files changed, 56 insertions(+), 4 deletions(-)
diff --git a/hw/misc/aspeed_scu.c b/hw/misc/aspeed_scu.c
index d06e179a6e..3b11e98d66 100644
--- a/hw/misc/aspeed_scu.c
+++ b/hw/misc/aspeed_scu.c
@@ -205,6 +205,8 @@ static const uint32_t ast2500_a1_resets[ASPEED_SCU_NR_REGS]
= {
[BMC_DEV_ID] = 0x00002402U
};
+static uint32_t aspeed_2600_scu_calc_hpll(AspeedSCUState *s, uint32_t hpll_reg);
+
static uint32_t aspeed_scu_get_random(void)
{
uint32_t num;
@@ -215,9 +217,19 @@ static uint32_t aspeed_scu_get_random(void)
uint32_t aspeed_scu_get_apb_freq(AspeedSCUState *s)
{
AspeedSCUClass *asc = ASPEED_SCU_GET_CLASS(s);
- uint32_t hpll = asc->calc_hpll(s, s->regs[HPLL_PARAM]);
+ uint32_t hpll, hpll_reg, clk_sel_reg;
+
+ if (asc->calc_hpll == aspeed_2600_scu_calc_hpll) {
That's indeed one way to distinguish the AST2600 from the previous SoCs.
I would prefer to introduce a new APB freq class handler to deal with
the differences in the AST2600. aspeed_scu_get_apb_freq() would become :
uint32_t aspeed_scu_get_apb_freq(AspeedSCUState *s)
{
return ASPEED_SCU_GET_CLASS(s)->get_apb(s);
}
The current aspeed_scu_get_apb_freq() would become the AST2400 and AST2500
handler and you would have to introduce a new one for the AST2600.
+ hpll_reg = s->regs[AST2600_HPLL_PARAM];
+ clk_sel_reg = s->regs[AST2600_CLK_SEL];
+ } else {
+ hpll_reg = s->regs[HPLL_PARAM];
+ clk_sel_reg = s->regs[CLK_SEL];
+ }
+
+ hpll = asc->calc_hpll(s, hpll_reg);
- return hpll / (SCU_CLK_GET_PCLK_DIV(s->regs[CLK_SEL]) + 1)
+ return hpll / (SCU_CLK_GET_PCLK_DIV(clk_sel_reg) + 1)
/ asc->apb_divider;> }
@@ -357,7 +369,10 @@ static const MemoryRegionOps aspeed_ast2500_scu_ops = {
static uint32_t aspeed_scu_get_clkin(AspeedSCUState *s)
{
- if (s->hw_strap1 & SCU_HW_STRAP_CLK_25M_IN) {
+ AspeedSCUClass *asc = ASPEED_SCU_GET_CLASS(s);
+
+ if (s->hw_strap1 & SCU_HW_STRAP_CLK_25M_IN ||
+ asc->calc_hpll == aspeed_2600_scu_calc_hpll) {
Indeed, the AST2600 CLKIN is always 25Mhz. Instead of testing ->calc_hpll,
I would introduce a class attribute, something like 'bool is_25Mhz'.
This change should be in a second patch though.
Thanks,
C.
return 25000000;
} else if (s->hw_strap1 & SCU_HW_STRAP_CLK_48M_IN) {
return 48000000;
@@ -426,6 +441,26 @@ static uint32_t aspeed_2500_scu_calc_hpll(AspeedSCUState
*s, uint32_t hpll_reg)
return clkin * multiplier;
}
+static uint32_t aspeed_2600_scu_calc_hpll(AspeedSCUState *s, uint32_t hpll_reg)
+{
+ uint32_t multiplier = 1;
+ uint32_t clkin = aspeed_scu_get_clkin(s);
+
+ if (hpll_reg & SCU_AST2600_H_PLL_OFF) {
+ return 0;
+ }
+
+ if (!(hpll_reg & SCU_H_PLL_BYPASS_EN)) {
+ uint32_t p = (hpll_reg >> 19) & 0xf;
+ uint32_t n = (hpll_reg >> 13) & 0x3f;
+ uint32_t m = hpll_reg & 0x1fff;
+
+ multiplier = ((m + 1) / (n + 1)) / (p + 1);
+ }
+
+ return clkin * multiplier;
+}
+
static void aspeed_scu_reset(DeviceState *dev)
{
AspeedSCUState *s = ASPEED_SCU(dev);
@@ -716,7 +751,7 @@ static void aspeed_2600_scu_class_init(ObjectClass *klass,
void *data)
dc->desc = "ASPEED 2600 System Control Unit";
dc->reset = aspeed_ast2600_scu_reset;
asc->resets = ast2600_a3_resets;
- asc->calc_hpll = aspeed_2500_scu_calc_hpll; /* No change since AST2500 */
+ asc->calc_hpll = aspeed_2600_scu_calc_hpll;
asc->apb_divider = 4;
asc->nr_regs = ASPEED_AST2600_SCU_NR_REGS;
asc->ops = &aspeed_ast2600_scu_ops;
diff --git a/include/hw/misc/aspeed_scu.h b/include/hw/misc/aspeed_scu.h
index c14aff2bcb..91c500c5bc 100644
--- a/include/hw/misc/aspeed_scu.h
+++ b/include/hw/misc/aspeed_scu.h
@@ -316,4 +316,21 @@ uint32_t aspeed_scu_get_apb_freq(AspeedSCUState *s);
SCU_HW_STRAP_VGA_SIZE_SET(VGA_16M_DRAM) | \
SCU_AST2500_HW_STRAP_RESERVED1)
+/* SCU200 H-PLL Parameter Register (for Aspeed AST2600 SOC)
+ *
+ * 28:26 H-PLL Parameters
+ * 25 Enable H-PLL reset
+ * 24 Enable H-PLL bypass mode
+ * 23 Turn off H-PLL
+ * 22:19 H-PLL Post Divider (P)
+ * 18:13 H-PLL Numerator (M)
+ * 12:0 H-PLL Denumerator (N)
+ *
+ * (Output frequency) = CLKIN(25MHz) * [(M+1) / (N+1)] / (P+1)
+ *
+ * The default frequency is 1200Mhz when CLKIN = 25MHz
+ */
+#define SCU_AST2600_H_PLL_BYPASS_EN (0x1 << 24)
+#define SCU_AST2600_H_PLL_OFF (0x1 << 23)
+
#endif /* ASPEED_SCU_H */
