michael/u-boot
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

mmc: msm_sdhci: Add DLL control hook to disable DLL below 100 MHz

Browse Source 
Introduce an SDHCI ops hook (config_dll) for MSM SDHCI and implement a
minimal DLL control routine that ensures the core DLL is disabled when
the bus clock is at or below 100 MHz. This approach mirrors the Linux
MSM SDHCI driver.

Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Link: https://patch.msgid.link/20251210155454.1561611-3-loic.poulain@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
This commit is contained in:
Sumit Garg
2025-12-10 16:54:54 +01:00
committed by Casey Connolly
parent 3ddc67573f
commit 338c4b8208
1 changed files with 37 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

37
drivers/mmc/msm_sdhci.c
View File

@@ -36,6 +36,11 @@
#define CORE_VENDOR_SPEC_POR_VAL 0xa9c
#define CORE_DLL_PDN BIT(29)
#define CORE_DLL_RST BIT(30)
#define MHZ(X) ((X) * 1000000UL)
struct msm_sdhc_plat {
struct mmc_config cfg;
struct mmc mmc;
@@ -51,6 +56,7 @@ struct msm_sdhc {
struct msm_sdhc_variant_info {
bool mci_removed;
u32 core_dll_config;
u32 core_vendor_spec;
u32 core_vendor_spec_capabilities0;
};
@@ -149,6 +155,34 @@ static int msm_sdc_mci_init(struct msm_sdhc *prv)
return 0;
}
static int msm_sdhci_config_dll(struct sdhci_host *host, u32 clock, bool enable)
{
struct udevice *dev = mmc_to_dev(host->mmc);
const struct msm_sdhc_variant_info *var_info = (void *)dev_get_driver_data(dev);
u32 config;
if (enable && clock < MHZ(100)) {
/*
* DLL is not required for clock <= 100MHz
* Thus, make sure DLL is disabled when not required
*/
config = readl(host->ioaddr + var_info->core_dll_config);
config |= CORE_DLL_RST;
writel(config, host->ioaddr + var_info->core_dll_config);
config = readl(host->ioaddr + var_info->core_dll_config);
config |= CORE_DLL_PDN;
writel(config, host->ioaddr + var_info->core_dll_config);
}
return 0;
}
struct sdhci_ops msm_sdhci_ops = {
.config_dll = &msm_sdhci_config_dll,
.set_control_reg = &sdhci_set_control_reg,
};
static int msm_sdc_probe(struct udevice *dev)
{
struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
@@ -223,6 +257,7 @@ static int msm_sdc_probe(struct udevice *dev)
host->mmc = &plat->mmc;
host->mmc->dev = dev;
host->ops = &msm_sdhci_ops;
ret = sdhci_setup_cfg(&plat->cfg, host, 0, 0);
if (ret)
return ret;
@@ -288,6 +323,7 @@ static int msm_sdc_bind(struct udevice *dev)
static const struct msm_sdhc_variant_info msm_sdhc_mci_var = {
.mci_removed = false,
.core_dll_config = 0x100,
.core_vendor_spec = 0x10c,
.core_vendor_spec_capabilities0 = 0x11c,
};
@@ -295,6 +331,7 @@ static const struct msm_sdhc_variant_info msm_sdhc_mci_var = {
static const struct msm_sdhc_variant_info msm_sdhc_v5_var = {
.mci_removed = true,
.core_dll_config = 0x200,
.core_vendor_spec = 0x20c,
.core_vendor_spec_capabilities0 = 0x21c,
};