[PATCH v4 4/5] arm: mach-k3: j721e-init.c: Add support for CONFIG_K3_OPP_LOW
Aniket Limaye
a-limaye at ti.com
Tue Nov 19 01:32:58 CET 2024
The default j7200 devicetree and k3_avs driver set 2GHz/1GHz frequency
for A72/MSMC clks and the OPP_NOM voltage.
J7200 SOCs may support OPP_LOW Operating Performance Point:
1GHz/500MHz clks for A72/MSMC and OPP_LOW AVS voltage read from efuse.
Hence, add a config check in board_init_f() to select OPP_LOW specs:
- Check if OPP_LOW AVS voltage read from efuse is valid.
- Use the device IDs and clock IDs (TISCI docs [0]) to find the A72 and
MSMC clock frequencies in the devicetree.
- Fixup the clock frequencies in devicetree as per OPP_LOW spec.
k3_avs driver programs the OPP_LOW AVS voltage for VDD_CPU through
k3_avs_notify_freq() callback from clk_k3.
[0]: https://software-dl.ti.com/tisci/esd/latest/5_soc_doc/j7200/clocks.html
Signed-off-by: Aniket Limaye <a-limaye at ti.com>
---
v4:
- Fixup patch styling problems
- In previous versions, fdt_fixup_a72ss_clock_frequency() assumed a
fixed order of assigned-clock-rates in the DT to update clk freqs.
This may not always be a valid assumption. So, add a new function
get_clock_index_by_dev_id() to search the indices for A72 CPU and MSMC
clk IDs and then use that index to update the clock rates in place.
- Link to v3: https://lore.kernel.org/u-boot/20241116071615.839623-5-a-limaye@ti.com/
v3:
- Use more descriptive name for fdt_fixup_a72ss_clock_frequency()
and make function static.
- Add error codes to prints.
- Move error prints (with error codes) before else conditions. Helps
with code readability to map error print with the function.
- Remove k3_avs_set_opp() from here altogether. Reasoning being that the
value being set through k3_avs_set_opp() will anyway be (correctly)
overridden by the k3_avs_notify_freq() call later in the boot process,
when a72 freq is actually set from clk_k3.
- Link to v2: https://lore.kernel.org/u-boot/20241023130033.1826413-5-a-limaye@ti.com/
v2:
- Fix indentation in fix_freq()
- Remove the efuse data check addition from this commit, as it's not
related to adding support for CONFIG_K3_OPP_LOW. The same addition
was moved to the previous patch in this series.
- Link to v1: https://lore.kernel.org/u-boot/20241017062911.2241167-5-a-limaye@ti.com/
---
arch/arm/mach-k3/j721e/j721e_init.c | 92 ++++++++++++++++++++++++++++-
1 file changed, 91 insertions(+), 1 deletion(-)
diff --git a/arch/arm/mach-k3/j721e/j721e_init.c b/arch/arm/mach-k3/j721e/j721e_init.c
index e9ed8cb267c..805b28af8e4 100644
--- a/arch/arm/mach-k3/j721e/j721e_init.c
+++ b/arch/arm/mach-k3/j721e/j721e_init.c
@@ -19,6 +19,7 @@
#include <fdtdec.h>
#include <mmc.h>
#include <remoteproc.h>
+#include <k3-avs.h>
#include "../sysfw-loader.h"
#include "../common.h"
@@ -39,6 +40,12 @@
#define NB_THREADMAP_BIT0 BIT(0)
#define NB_THREADMAP_BIT1 BIT(1)
+/* TISCI DEV ID for A72, MSMC Clock */
+#define DEV_A72SS0_CORE0_0_ID 202
+#define DEV_A72SS0_CORE0_0_ARM_CLK_CLK_ID 2
+#define DEV_A72SS0_CORE0_ID 4
+#define DEV_A72SS0_CORE0_MSMC_CLK_ID 1
+
#ifdef CONFIG_K3_LOAD_SYSFW
struct fwl_data cbass_hc_cfg0_fwls[] = {
#if defined(CONFIG_TARGET_J721E_R5_EVM)
@@ -147,6 +154,78 @@ static void setup_navss_nb(void)
writel(NB_THREADMAP_BIT1, (uintptr_t)NAVSS0_NBSS_NB1_CFG_NB_THREADMAP);
}
+#if defined(CONFIG_CPU_V7R) && defined(CONFIG_K3_AVS0)
+static int get_clock_index_by_dev_id(ofnode node, u32 dev_id, u32 clk_id)
+{
+ ofnode clknode;
+ int count, i;
+ struct ofnode_phandle_args phandle_args;
+
+ clknode = ofnode_by_compatible(ofnode_null(), "ti,k2g-sci-clk");
+ if (!ofnode_valid(clknode)) {
+ printf("%s: clock-controller not found\n", __func__);
+ return -ENODEV;
+ }
+
+ count = ofnode_count_phandle_with_args(node, "assigned-clocks", "#clock-cells", 0);
+ for (i = 0; i < count; i++) {
+ if (ofnode_parse_phandle_with_args(node, "assigned-clocks",
+ "#clock-cells", 0, i, &phandle_args)) {
+ printf("%s: Could not parse assigned-clocks at index %d\n", __func__, i);
+ continue;
+ }
+ if (ofnode_equal(clknode, phandle_args.node) &&
+ phandle_args.args[0] == dev_id && phandle_args.args[1] == clk_id)
+ return i;
+ }
+ return -1;
+}
+
+static int fdt_fixup_a72ss_clock_frequency(void)
+{
+ int index, size;
+ u32 *rates;
+ ofnode node;
+
+ node = ofnode_by_compatible(ofnode_null(), "ti,am654-rproc");
+ if (!ofnode_valid(node)) {
+ printf("%s: A72 not found\n", __func__);
+ return -ENODEV;
+ }
+
+ rates = fdt_getprop_w(ofnode_to_fdt(node), ofnode_to_offset(node),
+ "assigned-clock-rates", &size);
+ if (!rates) {
+ printf("%s: Wrong A72 assigned-clocks-rates configuration\n", __func__);
+ return -1;
+ }
+
+ /* Update A72 Clock Frequency to OPP_LOW spec */
+ index = get_clock_index_by_dev_id(node,
+ DEV_A72SS0_CORE0_0_ID,
+ DEV_A72SS0_CORE0_0_ARM_CLK_CLK_ID);
+ if (index < 0 || index >= (size / sizeof(u32))) {
+ printf("%s: Wrong A72 assigned-clocks configuration\n", __func__);
+ return -1;
+ }
+ rates[index] = cpu_to_fdt32(1000000000);
+ printf("Changed A72 CPU frequency to %dHz in DT\n", 1000000000);
+
+ /* Update MSMC Clock Frequency to OPP_LOW spec */
+ index = get_clock_index_by_dev_id(node,
+ DEV_A72SS0_CORE0_ID,
+ DEV_A72SS0_CORE0_MSMC_CLK_ID);
+ if (index < 0 || index >= (size / sizeof(u32))) {
+ printf("%s: Wrong A72 assigned-clocks configuration\n", __func__);
+ return -1;
+ }
+ rates[index] = cpu_to_fdt32(500000000);
+ printf("Changed MSMC frequency to %dHz in DT\n", 500000000);
+
+ return 0;
+}
+#endif
+
/*
* This uninitialized global variable would normal end up in the .bss section,
* but the .bss is cleared between writing and reading this variable, so move
@@ -301,8 +380,19 @@ void board_init_f(ulong dummy)
#if defined(CONFIG_CPU_V7R) && defined(CONFIG_K3_AVS0)
ret = uclass_get_device_by_driver(UCLASS_MISC, DM_DRIVER_GET(k3_avs),
&dev);
- if (ret)
+ if (ret) {
printf("AVS init failed: %d\n", ret);
+ } else if (IS_ENABLED(CONFIG_K3_OPP_LOW)) {
+ ret = k3_avs_check_opp(dev, J721E_VDD_MPU, AM6_OPP_LOW);
+ if (ret) {
+ printf("OPP_LOW: k3_avs_check_opp failed: %d\n", ret);
+ } else {
+ ret = fdt_fixup_a72ss_clock_frequency();
+ if (ret)
+ printf("OPP_LOW: fdt_fixup_a72ss_clock_frequency failed: %d\n",
+ ret);
+ }
+ }
#endif
#if defined(CONFIG_K3_J721E_DDRSS)
--
2.47.0
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