/**
* omap44xx_restart - trigger a software restart of the SoC
* @mode: the "reboot mode", see arch/arm/kernel/{setup,process}.c
* @cmd: passed from the userspace program rebooting the system (if provided)
*
* Resets the SoC. For @cmd, see the 'reboot' syscall in
* kernel/sys.c. No return value.
*/
void omap44xx_restart(enum reboot_mode mode, const char *cmd)
{
/* XXX Should save 'cmd' into scratchpad for use after reboot */
omap4_prminst_global_warm_sw_reset(); /* never returns */
while (1)
;
}
/* Resets clock rates and reboots the system. Only called from system.h */
static void omap_prcm_arch_reset(char mode, const char *cmd)
{
s16 prcm_offs = 0;
if (cpu_is_omap24xx()) {
omap2xxx_clk_prepare_for_reboot();
prcm_offs = WKUP_MOD;
} else if (cpu_is_am33xx()) {
prcm_offs = AM33XX_PRM_DEVICE_MOD;
omap2_prm_set_mod_reg_bits(OMAP4430_RST_GLOBAL_COLD_SW_MASK,
prcm_offs, AM33XX_PRM_RSTCTRL_OFFSET);
} else if (cpu_is_omap34xx()) {
prcm_offs = OMAP3430_GR_MOD;
omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
} else if (cpu_is_omap44xx()) {
omap4_prminst_global_warm_sw_reset(); /* never returns */
} else {
WARN_ON(1);
}
/*
* As per Errata i520, in some cases, user will not be able to
* access DDR memory after warm-reset.
* This situation occurs while the warm-reset happens during a read
* access to DDR memory. In that particular condition, DDR memory
* does not respond to a corrupted read command due to the warm
* reset occurrence but SDRC is waiting for read completion.
* SDRC is not sensitive to the warm reset, but the interconnect is
* reset on the fly, thus causing a misalignment between SDRC logic,
* interconnect logic and DDR memory state.
* WORKAROUND:
* Steps to perform before a Warm reset is trigged:
* 1. enable self-refresh on idle request
* 2. put SDRC in idle
* 3. wait until SDRC goes to idle
* 4. generate SW reset (Global SW reset)
*
* Steps to be performed after warm reset occurs (in bootloader):
* if HW warm reset is the source, apply below steps before any
* accesses to SDRAM:
* 1. Reset SMS and SDRC and wait till reset is complete
* 2. Re-initialize SMS, SDRC and memory
*
* NOTE: Above work around is required only if arch reset is implemented
* using Global SW reset(GLOBAL_SW_RST). DPLL3 reset does not need
* the WA since it resets SDRC as well as part of cold reset.
*/
/* XXX should be moved to some OMAP2/3 specific code */
omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, prcm_offs,
OMAP2_RM_RSTCTRL);
omap2_prm_read_mod_reg(prcm_offs, OMAP2_RM_RSTCTRL); /* OCP barrier */
}
void omap_prcm_restart(char mode, const char *cmd)
{
s16 prcm_offs = 0;
if (cpu_is_omap24xx()) {
omap2xxx_clk_prepare_for_reboot();
prcm_offs = WKUP_MOD;
} else if (cpu_is_omap34xx()) {
prcm_offs = OMAP3430_GR_MOD;
omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
} else if (cpu_is_omap44xx()) {
omap4_prminst_global_warm_sw_reset(); /* */
} else {
WARN_ON(1);
}
/*
*/
/* */
omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, prcm_offs,
OMAP2_RM_RSTCTRL);
omap2_prm_read_mod_reg(prcm_offs, OMAP2_RM_RSTCTRL); /* */
}
/* Resets clock rates and reboots the system. Only called from system.h */
void omap_prcm_restart(char mode, const char *cmd)
{
s16 prcm_offs = 0;
if (cpu_is_omap24xx()) {
omap2xxx_clk_prepare_for_reboot();
prcm_offs = WKUP_MOD;
} else if (cpu_is_omap34xx()) {
prcm_offs = OMAP3430_GR_MOD;
omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
} else if (cpu_is_omap44xx()) {
omap4_prminst_global_warm_sw_reset(); /* never returns */
} else if (cpu_is_omap54xx()) {
/*
* Erratum i744:
* Seems that the HSDIVIDER ratio is corrupted after WARM reset
* H/w team WA is as follows:
* when warm reset is generated, PMIC must be set to generate
* cold reset OR, in the specific case of TWL6035,
* "TWL6035 device, it is recommended to connect the OMAP
* sys_nreswarm pin to the reset_in pin."
* Instead, Since many of the boards are not accessible for
* modification OR may use other PMICs which may not be capable,
* lets do cold reset in the first place.
*
* NOTE: this does not save us from other h/w Warm reset sources
* such as WDT/Thermal events.
*/
if (OMAP5430_REV_ES1_0 == omap_rev() ||
OMAP5432_REV_ES1_0 == omap_rev())
omap4_pm_cold_reset("Cold reset as WA reboot for i744");
else
omap4_prminst_global_warm_sw_reset();
/* Neither should return.. if they did, bug */
BUG();
} else {
WARN_ON(1);
}
/*
* As per Errata i520, in some cases, user will not be able to
* access DDR memory after warm-reset.
* This situation occurs while the warm-reset happens during a read
* access to DDR memory. In that particular condition, DDR memory
* does not respond to a corrupted read command due to the warm
* reset occurrence but SDRC is waiting for read completion.
* SDRC is not sensitive to the warm reset, but the interconnect is
* reset on the fly, thus causing a misalignment between SDRC logic,
* interconnect logic and DDR memory state.
* WORKAROUND:
* Steps to perform before a Warm reset is trigged:
* 1. enable self-refresh on idle request
* 2. put SDRC in idle
* 3. wait until SDRC goes to idle
* 4. generate SW reset (Global SW reset)
*
* Steps to be performed after warm reset occurs (in bootloader):
* if HW warm reset is the source, apply below steps before any
* accesses to SDRAM:
* 1. Reset SMS and SDRC and wait till reset is complete
* 2. Re-initialize SMS, SDRC and memory
*
* NOTE: Above work around is required only if arch reset is implemented
* using Global SW reset(GLOBAL_SW_RST). DPLL3 reset does not need
* the WA since it resets SDRC as well as part of cold reset.
*/
/* XXX should be moved to some OMAP2/3 specific code */
omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, prcm_offs,
OMAP2_RM_RSTCTRL);
omap2_prm_read_mod_reg(prcm_offs, OMAP2_RM_RSTCTRL); /* OCP barrier */
}
