Re: [PATCH net-next 3/3] net: stmmac: add glue layer for T-HEAD TH1520 SoC
From: Simon Horman <horms@kernel.org>
Date: 2023-08-20 15:00:01
Also in:
linux-arm-kernel, linux-devicetree, linux-riscv, lkml
On Sun, Aug 20, 2023 at 08:02:13PM +0800, Jisheng Zhang wrote:
Add dwmac glue driver to support the dwmac on the T-HEAD TH1520 SoC. Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
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quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-thead.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-thead.c
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+static void thead_dwmac_fix_speed(void *priv, unsigned int speed, unsigned int mode)
+{
+ struct thead_dwmac *dwmac = priv;
+ struct plat_stmmacenet_data *plat = dwmac->plat;
+ unsigned long rate;
+ u32 div;
+
+ switch (plat->interface) {
+ /* For MII, rxc/txc is provided by phy */
+ case PHY_INTERFACE_MODE_MII:
+ return;
+
+ case PHY_INTERFACE_MODE_RGMII:
+ case PHY_INTERFACE_MODE_RGMII_ID:
+ case PHY_INTERFACE_MODE_RGMII_RXID:
+ case PHY_INTERFACE_MODE_RGMII_TXID:
+ rate = clk_get_rate(plat->stmmac_clk);
+ if (!rate || rate % GMAC_GMII_RGMII_RATE != 0 ||
+ rate % GMAC_MII_RATE != 0) {
+ dev_err(dwmac->dev, "invalid gmac rate %ld\n", rate);
+ return;
+ }
+
+ regmap_update_bits(dwmac->apb_regmap, GMAC_PLLCLK_DIV, GMAC_PLLCLK_DIV_EN, 0);
+
+ switch (speed) {
+ case SPEED_1000:
+ div = rate / GMAC_GMII_RGMII_RATE;
+ break;
+ case SPEED_100:
+ div = rate / GMAC_MII_RATE;
+ break;
+ case SPEED_10:
+ div = rate * 10 / GMAC_MII_RATE;
+ break;
+ default:
+ dev_err(dwmac->dev, "invalid speed %u\n", speed);
+ break;Hi Jisheng Zhang, In this case, div is not initialised, but it is used a few lines below. Perhaps the function should return here? As flagged by clang-16 (W=1) and Smatch.
+ } + regmap_update_bits(dwmac->apb_regmap, GMAC_PLLCLK_DIV, + GMAC_PLLCLK_DIV_MASK, GMAC_PLLCLK_DIV_NUM(div)); + + regmap_update_bits(dwmac->apb_regmap, GMAC_PLLCLK_DIV, + GMAC_PLLCLK_DIV_EN, GMAC_PLLCLK_DIV_EN); + break; + default: + dev_err(dwmac->dev, "unsupported phy interface %d\n", + plat->interface); + return; + } +}
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