From: Jim Liu Date: Tue, 14 Nov 2023 09:00:04 +0000 (+0800) Subject: clk: nuvoton: add read only feature for clk driver X-Git-Url: http://git.dujemihanovic.xyz/?a=commitdiff_plain;h=652d8d4561a34fc71d9bcb6ad2b0035d2c4189c1;p=u-boot.git clk: nuvoton: add read only feature for clk driver Add a flag to set ahb/apb/fiu/spi clock divider as read-only The spi clock setting is related to booting flash, it is setup by early bootloader. It just protects the clock source and can't modify it in uboot. Signed-off-by: Jim Liu Reviewed-by: Sean Anderson Link: https://lore.kernel.org/r/20231114090004.3746024-1-JJLIU0@nuvoton.com --- diff --git a/drivers/clk/nuvoton/clk_npcm.c b/drivers/clk/nuvoton/clk_npcm.c index 8d71f2a24b..18cb9cddbf 100644 --- a/drivers/clk/nuvoton/clk_npcm.c +++ b/drivers/clk/nuvoton/clk_npcm.c @@ -135,7 +135,7 @@ static u32 npcm_clk_get_div(struct clk *clk) return div; } -static u32 npcm_clk_set_div(struct clk *clk, u32 div) +static int npcm_clk_set_div(struct clk *clk, u32 div) { struct npcm_clk_priv *priv = dev_get_priv(clk->dev); struct npcm_clk_div *divider; @@ -145,6 +145,9 @@ static u32 npcm_clk_set_div(struct clk *clk, u32 div) if (!divider) return -EINVAL; + if (divider->flags & DIV_RO) + return 0; + if (divider->flags & PRE_DIV2) div = div >> 1; @@ -153,6 +156,12 @@ static u32 npcm_clk_set_div(struct clk *clk, u32 div) else clkdiv = ilog2(div); + if (clkdiv > (divider->mask >> (ffs(divider->mask) - 1))) { + printf("clkdiv(%d) for clk(%ld) is over limit\n", + clkdiv, clk->id); + return -EINVAL; + } + val = readl(priv->base + divider->reg); val &= ~divider->mask; val |= (clkdiv << (ffs(divider->mask) - 1)) & divider->mask; @@ -253,8 +262,8 @@ static ulong npcm_clk_set_rate(struct clk *clk, ulong rate) if (ret) return ret; - debug("%s: rate %lu, new rate (%lu / %u)\n", __func__, rate, parent_rate, div); - return (parent_rate / div); + debug("%s: rate %lu, new rate %lu\n", __func__, rate, npcm_clk_get_rate(clk)); + return npcm_clk_get_rate(clk); } static int npcm_clk_set_parent(struct clk *clk, struct clk *parent) diff --git a/drivers/clk/nuvoton/clk_npcm.h b/drivers/clk/nuvoton/clk_npcm.h index 06b60dc8b8..b4726d8381 100644 --- a/drivers/clk/nuvoton/clk_npcm.h +++ b/drivers/clk/nuvoton/clk_npcm.h @@ -50,6 +50,7 @@ #define PRE_DIV2 BIT(2) /* Pre divisor = 2 */ #define POST_DIV2 BIT(3) /* Post divisor = 2 */ #define FIXED_PARENT BIT(4) /* clock source is fixed */ +#define DIV_RO BIT(5) /* divider is read-only */ /* Parameters of PLL configuration */ struct npcm_clk_pll { diff --git a/drivers/clk/nuvoton/clk_npcm8xx.c b/drivers/clk/nuvoton/clk_npcm8xx.c index 27e3cfcf55..d1b32e3237 100644 --- a/drivers/clk/nuvoton/clk_npcm8xx.c +++ b/drivers/clk/nuvoton/clk_npcm8xx.c @@ -45,12 +45,12 @@ static struct npcm_clk_select npcm8xx_clk_selectors[] = { }; static struct npcm_clk_div npcm8xx_clk_dividers[] = { - {NPCM8XX_CLK_AHB, CLKDIV1, CLK4DIV, DIV_TYPE1 | PRE_DIV2}, - {NPCM8XX_CLK_APB2, CLKDIV2, APB2CKDIV, DIV_TYPE2}, - {NPCM8XX_CLK_APB5, CLKDIV2, APB5CKDIV, DIV_TYPE2}, - {NPCM8XX_CLK_SPI0, CLKDIV3, SPI0CKDIV, DIV_TYPE1}, - {NPCM8XX_CLK_SPI1, CLKDIV3, SPI1CKDIV, DIV_TYPE1}, - {NPCM8XX_CLK_SPI3, CLKDIV1, SPI3CKDIV, DIV_TYPE1}, + {NPCM8XX_CLK_AHB, CLKDIV1, CLK4DIV, DIV_TYPE1 | PRE_DIV2 | DIV_RO}, + {NPCM8XX_CLK_APB2, CLKDIV2, APB2CKDIV, DIV_TYPE2 | DIV_RO}, + {NPCM8XX_CLK_APB5, CLKDIV2, APB5CKDIV, DIV_TYPE2 | DIV_RO}, + {NPCM8XX_CLK_SPI0, CLKDIV3, SPI0CKDIV, DIV_TYPE1 | DIV_RO}, + {NPCM8XX_CLK_SPI1, CLKDIV3, SPI1CKDIV, DIV_TYPE1 | DIV_RO}, + {NPCM8XX_CLK_SPI3, CLKDIV1, SPI3CKDIV, DIV_TYPE1 | DIV_RO}, {NPCM8XX_CLK_SPIX, CLKDIV3, SPIXCKDIV, DIV_TYPE1}, {NPCM8XX_CLK_UART, CLKDIV1, UARTDIV1, DIV_TYPE1}, {NPCM8XX_CLK_UART2, CLKDIV3, UARTDIV2, DIV_TYPE1},