On 5/30/25 12:58 AM, Shmuel Melamud via B4 Relay wrote:
From: Shmuel Melamud <smela...@redhat.com>Add support of Renesas R-Car Gen4 watchdog timer. Timeouts up to 8184.0s are supported (CKS1 register is not involved). The watchdog uses the clock type CLK_TYPE_GEN4_MDSEL, so handling of this constant is added to gen3_clk_get_rate64() function. The timeout is set in dts/upstream/src/arm64/renesas/r8a779f0-spider-cpu.dtsi section &rwdt. This patch was tested on real Renesas R8A779F0 hardware. If the watchdog driver is enabled at the build time, the watchdog timer is initialized when U-Boot starts. Under normal circumstances, U-Boot loads the kernel, it starts systemd and systemd continues to pet the watchdog. If systemd is not started before the timeout expires, the watchdog resets the board. Signed-off-by: Shmuel Leib Melamud <smela...@redhat.com> --- drivers/clk/renesas/clk-rcar-gen3.c | 4 +- drivers/watchdog/Kconfig | 8 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/renesas_wdt.c | 172 ++++++++++++++++++++++++++++++++++++ 4 files changed, 184 insertions(+), 1 deletion(-) diff --git a/drivers/clk/renesas/clk-rcar-gen3.c b/drivers/clk/renesas/clk-rcar-gen3.c index 375cc4a4930873ad0d5509c19ad04a0ea5545aa0..5745acf4023c9114f6fa13b5e4baa306c5b57d33 100644 --- a/drivers/clk/renesas/clk-rcar-gen3.c +++ b/drivers/clk/renesas/clk-rcar-gen3.c @@ -68,7 +68,7 @@ static int gen3_clk_get_parent(struct gen3_clk_priv *priv, struct clk *clk, if (ret) return ret;- if (core->type == CLK_TYPE_GEN3_MDSEL) {+ if (core->type == CLK_TYPE_GEN3_MDSEL || core->type == CLK_TYPE_GEN4_MDSEL) { shift = priv->cpg_mode & BIT(core->offset) ? 0 : 16; parent->dev = clk->dev; parent->id = core->parent >> shift; @@ -318,6 +318,8 @@ static u64 gen3_clk_get_rate64(struct clk *clk) "FIXED");case CLK_TYPE_GEN3_MDSEL:+ fallthrough; + case CLK_TYPE_GEN4_MDSEL: shift = priv->cpg_mode & BIT(core->offset) ? 0 : 16; div = (core->div >> shift) & 0xffff; rate = gen3_clk_get_rate64(&parent) / div;
Clock driver change should be in separate patch. I'll try to review the watchdog driver itself in the next few days. Thanks !
